If you want the most perfectly moist, flavorful, and juicy Thanksgiving Turkey, my recipe for dry-brining is what you’re looking for. All you need to do is rub the turkey down with salt, seasonings and fresh herbs. Then place the turkey in the fridge and let the dry brine work its magic for the next 48 to 72 hours.
That’s all you need the prep you need to do and you’re on your way to enjoying the best turkey you’ll ever eat!
When it comes to cooking a turkey, what you do before it goes into your oven makes all the difference in the world.
Don’t be intimidated by the thought of cooking a turkey. Because I’m here to share my dry brining and roasting methods to make your holiday turkey the star of the holiday dinner
There are different thoughts on brining a turkey, with the choices being wet brine or dry brining. While both techniques will help you cook the most succulent turkey you’ve ever had, the smartest, easiest way to achieve the best results every time is with a dry brine.
It doesn’t matter if this is your first Thanksgiving dinner, my dry-brine method will make you look like a seasoned veteran of Thanksgiving and turn out an impeccably juicy, flavorful bird.
What Ingredients do I need to Dry Brine a Turkey?
Let’s start by gathering the ingredients we need to dry brine our turkey. In Chef Speak this is called the Mise en Place which translates into Everything in its Place.
Not only does setting your ingredients up ahead of time speed the cooking process, but it also helps ensure you have everything you need to make the dish.
- Kosher Salt
- Black Pepper
- Smoked paprika
- Citrus zest
- Fresh thyme
- Fresh Sage
Do I have to use specific herbs and spices to dry brine a turkey?
That’s a tricky question because if you want a traditional Thanksgiving turkey, the answer is yes.
But If you like specific flavorings and aren’t into traditional Thanksgiving flavors, then by all means have fun substituting spices that you like.
Recipes should be used as guidelines and in all honesty, the salt is the only ingredient you really need for dry brining, the rest are added for flavor.
Why Should I dry brine my turkey?
When you’re dealing with a large piece of meat like a whole turkey, it’s easy to overcook it into a dry, flavorless disaster. Dry Brining gives the dry brine mixture time to penetrate into the meat.
Dry brining (dry rub) is a way to inject both flavor and moisture into a turkey, giving you a flavorful moist roasted turkey.
Rule #1 of Dry Brining – The larger the piece of meat, the more time is needed for the brine to be effective.
A dry brine, also called pre-salting involves rubbing the salt, seasonings, and/or sugar directly onto the meat and skin, and then letting the meat rest in the refrigerator for a period of time before cooking. During the process of dry brining, the salt draws out the juices through osmosis.
As the salt dissolves into the juices, it begins turning into a natural brine without any added liquid. This Natural brine is then reabsorbed into the meat and starts breaking down the tough muscle proteins. That is why this process needs up to 3 days to complete.
How to thaw a frozen turkey
The best way to thaw your turkey in the refrigerator in its original packaging. General defrosting times are 24 hours for every 4 pounds of Turkey.
If you have no choice and must thaw your turkey quickly, fill the kitchen sink with cold water and put the turkey in it, breast side down.
Make sure to completely submerge the turkey in water (in its original packaging) for the quick thaw method. Make sure to change the water every 30 minutes. This defrosting method will take 30 to 40 minutes per pound of turkey.
*When finished thawing the turkey make sure to clean and disinfect the sink, spigots, and all surrounding surfaces.
*Don’t leave the turkey out to thaw on the countertop.
Chef Tips for Dry Brining
- Don’t buy a preseasoned or kosher turkey (pre-salted) or self-basting turkeys. I always look for free-roaming or a heritage bird. But most importantly no added salt.
- Make sure your turkey is thawed if you buy a frozen turkey. *Buy your turkey early enough so that it’s thawed and ready to brine on the Monday before Thanksgiving.
- It doesn’t have to be a whole turkey, you can dry brine a turkey breast.
- Getting under the skin of the turkey and applying the brine directly to the meat will make a tastier, moister turkey. If you’re only going to brine the skin, try and brine it for the full 72 hours.
- Don’t rush dry brining. To enjoy the best turkey you’ll ever have, you need to give it enough time to be effective. 2 days is the minimum, and can go as long as 4 days if you’re working with a 20-pound plus bird. *Any length of time you can brine the turkey is better than not brining the bird.
- You can use any herbs that you like, but the salt really does matter. Use Morton’s Kosher Salt for the best results. Diamond Kosher salt is a smaller grain so reduce the amount of salt. Don’t use table salt it’s too fine and will make the turkey too salty.
- If you don’t have Kosher Salt you can use Coarse Sea Salt or Coarse Himalayan Pink Salt, because of the size of the coarse grains.
*The standard is 1 tablespoon of salt for every 5 pounds of turkey, but I like to go a little below that at 1 tablespoon of salt for every 6 lbs. So if you’re turkey is smaller adjust the amount of salt and herbs.
Does it Matter Where I apply the Dry Brine Mixture?
It does make a difference where you apply the dry brine. Separating the skin from the meat so that some of the dry brine can be rubbed directly on top of the meat (below the skin) will give you the best results.
If you apply the brine directly on the skin it will need more time to penetrate the skin and get to the meat. The breast will also get more of the dry brine than the rest of the turkey. The turkey breast has the largest amount of meat on a conventional turkey.
- After applying the dry brine, place the turkey breast-side up in a roasting pan. Cover the turkey securely using plastic wrap. Or place it into a small plastic bag and seal it, removing as much of the air as possible. Refrigerate for 48 – 60 hours.
- Remove the plastic wrap and keep it refrigerated uncovered for the last 12 hours of brining. This will help crisp the turkey skin.
Can I use Dry Herbs in the Dry Brining Method?
Yes, you can, although I prefer fresh herbs. You can find them at most grocery stores in convenient little plastic containers. If fresh herbs are not available by all means use dry herbs. You can also add any other herbs or aromatics that you like.
Should I cook a Heritage Turkey differently?
A heritage turkey is more elongated with drumsticks that are a good 1 to 2 inches longer than a modern bird, extending well beyond the tip of the breast.
Because of its more elongated shape, a heritage turkey cooks a little more quickly than a conventional turkey, so the biggest danger is overcooking. To make sure your Heritage Turkey is not overcooked, follow my recipe changing the cooking times.
Roast an unstuffed turkey at 425° for 20 minutes, then turn down the temperature to 325°F until the internal temperature of the thigh meat reaches 155°F.
Cooking 15-20 minutes per pound for the total cooking time. That being said, I would start checking the internal temperature 2 hours after the second phase of the process using an insta-read thermometer in the thigh.
Also, make sure to allow 1-½ lb. per person compared to about 1 lb. for a conventional turkey. As an example expect a 12-lb. heritage turkey to feed about eight people. Also, keep in mind that you’ll have as much dark meat as light meat. A conventional turkey will have more white meat.
Chef Tips for Roasting a Dry Brined Turkey
- Set your oven rack in the bottom third of the oven.
- Let the turkey sit out of refrigeration for about 30 minutes so it can come to room temperature before roasting.
- Allow the turkey to sit at room temperature for one hour before roasting. **Do Not Rinse The Brine Off Turkey
- Start off roasting the turkey at 425°F, and roast upside down for the first 45 minutes. At the end of that time very carefully turn the turkey over with the breast side up to continue cooking.
- You’ll find that some ovens have cold spots. This is why it’s a good idea to rotate the turkey halfway through and baste for even cooking and browning. Keep some turkey or chicken stock handy in case your turkey doesn’t produce enough juices during the roasting process and use that for basting if necessary.
- Always use an instant-read thermometer to insure that your turkey has been cooked properly. Insert the thermometer into the thickest part of a thigh without touching the bone registers. Your turkey will be done when the thermometer reaches 165°F when. It will continue to cook once you remove it from the oven increasing by another 10 degrees.
- Let the turkey rest for 20-30 minutes before carving.
I absolutely love my Meater Plus | Smart Meat Thermometer It takes all the guesswork out of cooking meats in the oven, on the grill, or in a smoker.
Do I have to start the turkey upside down?
No, you don’t. Safety should always come first and if you don’t think you can flip the turkey safely, skip that step. Still use the instruction for roasting starting at 425 degrees, then lowering to 325 degrees.
**If you do flip the turkey, take the pan out of the oven first. Don’t attempt this while the pan is in the oven.
You might also find heat-resistant gloves a good option. They’ll come in handy throughout the year.
- Rappica 14″ BBQ Gloves (my choice)
- Heat Resistant Oven Gloves
Can I still Dry-Brine a Self-Basting or Kosher Turkey?
No, you can’t. That will make the turkey too salty! What you can do, is leave the salt out of the dry-brine ingredients and use the remainder of the seasonings as a dry rub. Feel free to add in your favorite spices.
Apply the dry rub for 24-36 hours and follow the roasting instructions.
My Turkey has been injected with a Saline Solution, can I still Dry Brine it?
While it’s not a good idea to add more salt to an injected turkey, you can still use the dry brine method. If your turkey is in the 15-pound range cut the Kosher Salt down to 1 Tablespoon. If your turkey is under 15 pounds reduce the salt accordingly. You can use the rest of the ingredients as stated in the recipe.
Why shouldn’t I stuff my turkey?
I know that the stuffing from inside the turkey is the best you’ll ever have. But it’s not a practice I recommend for two very important reasons.
The stuffing sucks a lot of the moisture (and flavor) out of the turkey. That’s why a stuffed turkey is often dry and overcooked. And the really bad news is, it puts us at risk for foodborne illness.
The longer it takes the turkey to reach an internal temperature of 165 degrees gives bacteria more time to multiply. And that means that uncle Sal (salmonella) might be paying you and your guests an unexpected holiday visit, which will definitely put a damper on the festivities.
**Stuffed turkeys also take longer to cook.
If you have leftover turkey, try my Old Fashioned Turkey Croquettes.
Recipe FAQ’s
Dry-brining also referred to as salting is the process of rubbing the meat down with salt. The natural moisture content of the meat creates a concentrated brine that is naturally absorbed back into the meat before cooking.
A whole turkey needs two to three days of brining time, the dry-brining can be done days before Thanksgiving giving you extra time on Turkey Day.
For the last 24 hours of the dry brine leave the turkey uncovered in the refrigerator. This will dry out the skin, which in turn gives you incredibly crispy, golden-brown skin on the finished turkey.
Recipes to serve with turkey!
How to Dry Brine and Roast a Turkey
Ingredients
Dry Brine Ingredients
- 3 tbsp coarse kosher salt I use Morton's Kosher Salt (coarse grain sea salt may be used)
- 1 tbsp coarse grind black pepper
- 1 tbsp thyme finely chopped fresh or dry
- 1 tbsp sage finely chopped fresh or dry
- 1 tbsp clementine peel finely zested any citrus may be used
- 1 tsp smoked paprika optional
Roasting Turkey
- 1-2 carrots rough cut
- 1 onion rough cut
- 3-4 stalks celery rough cut
- 2 cloves garlic peeled
- 16-20 lb turkey fresh or frozen
- rough cut onion, carrot, sage, thyme and orange skin for inside the turkey (optional)
Instructions
Prep and Dry Brining
- Mix the dry brine ingredients together in a small bowl and set aside
- Remove the turkey from the wrapping and remove the giblets and neck from inside the cavity and save for another use. Remove or discard any plastic or metal cages or pop-up thermometers.
- If you can follow safe procedures, rinse the entire turkey in cold water thoroughly. Then pat the turkey dry using paper towels, inside and out. The FDA Does Not Recommend Rinsing Turkeys. If you do rinse your turkey make sure to clean and sanitize the counters, sink, faucet and any areas possibly exposed.
- Using your hands, gently loosen the skin over the breast and separate it from the meat, making sure to break through the thin membrane between the skin and breast while leaving the skin itself intact.
- Sprinkle 2 teaspoons of the salt mixture into the cavity of the turkey and rub it into the cavity.
- Rub 4 teaspoons of the salt mixture into the meat of the breasts (under the skin). Then sprinkle the remaining salt mixture over all the skin of both the breasts, legs and wings
- Place the turkey breast-side up in a roasting pan. Cover the turkey securely using plastic wrap, or place it into a small plastic bag and seal it, removing as much of the air as possible. Refrigerate for 48 – 60 hours.
- After the time has expired, uncover the turkey and allow it to remain uncovered and refrigerated for 8-12 hours.
The Secret to Roasting
- Allow the turkey to sit at room temperature for one hour before roasting.**Do Not Rinse The Brine Off the Turkey
- Preheat the oven to 425º.
- In the bottom of your roasting pan add roughly cut celery, onions, garlic, and carrots. Include the skin from the onion and carrots. Add 1 cup of chicken broth or water to the pan.**You can also place some aromatics inside the cavity of the turkey before cooking. Onions, carrots, herbs of your choice, orange peel and any other spices you like.
- Place the turkey upside down on a rack in a roasting pan. This will allow the turkey to self baste the breast as the fat from the underside and dark meat flow into the breast.**If you don't feel comfortable turning the hot turkey, cook your turkey right side up for the entire process. The breast meat won't be quite as moist, but it's not a deal-breaker. Safety First!
- Brush the turkey with melted butter and roast upside down for the first 45 minutes. At the end of that time very carefully turn the turkey over with the breast side up to continue cooking. ( I used heat resistant gloves) Brush again with melted butter if you like.Decrease oven temperature to 325º. Cook the turkey until it reaches the temp of 165º for the breast and 175º for the thighs. The meat will rise an additional 10º continuing to cook as it rests.*My 20-pound turkey only took an additional 3 hours to cook using this method. Make sure to check your turkey around the 2 ½ hour mark.
- Allow the turkey to rest 30 minutes before slicing. This will ensure that the juices stay in the turkey and don't all run out as you slice it.
Notes
Dry Brining Turkey Tips
- Don’t buy a preseasoned or kosher turkey (pre-salted) or self-basting turkeys. I always look for free-roaming or a heritage bird. But most importantly no added salt.
- Make sure your turkey is thawed if you buy a frozen turkey. Buy your turkey early enough so that it’s thawed and ready to brine on the Monday before Thanksgiving.
- It doesn’t have to be a whole turkey, you can dry brine a turkey breast.
- Getting under the skin of the turkey and applying the brine directly to the meat will make a tastier, moister turkey. If you’re only going to brine the skin, add an extra day to the process.
- Don’t rush dry brining. To enjoy the best turkey you’ll ever have, you need to give it enough time to be effective. 3 Days really is the minimum, 4 is even better especially if you’re working with a 20 pound plus bird.
- You can use any herbs that you like, but the salt really does matter. Use Kosher Salt for the best results. Salt that is too fine will make the bird too salty. Kosher salt, say it out loud, twice.
- The standard is 1 tablespoon of salt for every 5 pounds of turkey, but I like to go a little below that at 1 tablespoon of salt for every 6 lbs. So if you’re turkey is smaller adjust the amount of salt and herbs.
- Add more water to roasting pan if necessary to prevent pan drippings from burning.
- If you absolutely don’t have Kosher Salt and have to use Regular Salt decrease the amount of the salt by ⅓.
Brian
I have a 15 lb turkey; how long do you think?
Chef Dennis Littley
45 minutes at 425 and 2 -2.5 at 325 should be good for a 15 pound turkey
Carolyn Mitchell
Hi, Chef Dennis!
Sorry for the late comment, but I just noticed that you are answering folks this evening! So if you see this note, thank you in advance for your help!
So I began dry brining my turkey (first time!) this past Monday night. Unfortunately, I missed your instruction at the very end of your recipe notes that the turkey is uncovered only for 8-12 hours before roasting, not 24 hours! At the beginning of your recipe, I read that you normally brine it covered for 2 days then 1 day uncovered which led me to think I needed to uncover it this afternoon instead of after dinner hour.
Is it a problem to have the turkey uncovered longer than 12 hours? If so, should I recover it then uncover it early tomorrow morning for a few hour since it’s already been uncovered for 10 hours by now at midnight my time.
Wish I had also seen your adapted recipe for a 12 lb. turkey. I followed your recipe and cut back on the salt a little bit, but probably not enough. Hopefully it’s not too salty! Should I wipe some of the surface off? Thanks again for your help!
Chef Dennis Littley
hi Carolyn
uncovering longer is not a problem, it will help the skin get crisper. As for the salt, you may want to wipe any off the outside that still remains without getting the skin wet. The turkey will be fine, but the drippings may be a little saltier than they should. Add extra water into the pan instead of stock to thin the drippings out a bit to make the gravy.
Happy Thanksgiving
James Novak
Hi Chef Dennis,
Once again I am using your dry brine recipe, as it produces the best turkey out of any of the many methods I have ever used…
Any thoughts on having the turkey rest on a rack inside the roasting pan vs. sitting directly on the bottom of the pan? (above the stock/drippings instead of in them)
Thanks for taking our questions!
-James
Chef Dennis Littley
hi James
I use a rack and it works well, letting air get under the turkey is helpful in the cooking process
Happy Thanksgiving
Rachel
I tend to be a rebel and not follow Recipes if I don’t understand the why and it drives the husband nuts so I have to ask…why can’t I just leave breast side down entire time to make breast the moistest possible? We tend to eat the skin separate anyway and any skin that is not crispy can just be roasted with convection after the fact is how we normally do? Usually do a wet brine on a pastured turkey this is 1st time trying your recipe been dry brining since Monday!
Chef Dennis Littley
hi Rachel
The only problem with that is the top won’t brown. You could double the time it faces downward but I would still flip it to get a nicely browned turkey
Happy Thanksgiving
Paul Tronsgard
I dry brined according to your recipe in a roasting pan sealed with plastic for the last three days. I uncovered it this evening to allow it to dry overnight in the refrigerator. There is a fair bit of liquid in the roasting pan. Should I keep it in the pan for roasting or discard it and add broth per your recipe?
Thank you and Happy Thanksgiving!
Chef Dennis Littley
hi Paul
that is normal, discard the liquid before roasting and then add broth to the pan.
Happy Thanksgiving
Kelly
Hey Chef! One more question. I have a 26 lb self basting Turkey. I did the dry run according to your directions. How long should I roast my Turkey of that size? Thank you so much for all of your help!
Chef Dennis Littley
Hopefully you didn’t use salt in the rub since it’s a self basting turkey. Roast for 45 minutes at 425 degrees, then 3.5 – 4 hours at 325 degrees. Check the internal temp at 3 hours to make sure its not overcooking
Kelly
No sir,
I omitted the salt in the rub per your instructions. Thank you so much again!
Pam
Hi Chef,
I have been dry brining my turkey since Monday using your recipe. I have a 24 pound turkey and was wondering how long I should cook it for. Also, do you recommend using convect roast? Thank you.
Chef Dennis Littley
Convect roast is good Pam. Roast for 45 minutes at 425 degrees, then 3.5 – 4 hours at 325 degrees. Check the internal temp at 3 hours to make sure its not overcooking
Olive
Yikes, this is only the second time I’ve dry brined a turkey and I’m wondering if I did something wrong. I started the brine Monday at noon and, per instructions, this evening, Wednesday, just removed the plastic wrap to dry the skin so I can start to roast tomorrow morning. My concern is there is now quite a bit of liquid/water in the bottom of the pan that has accumulated, I didn’t add water….The turkey is organic with the packaging indicating no added salt but some water when processed. It was mostly thawed on Monday but not completely in the cavity. Should I be concerned? Do I just pour the water off? Pat dry the bird? If yes, when? Tonight? In the morning
I apologize for the late question,
Thank you
Chef Dennis Littley
hi Olive
this is normal, don’t worry. Let the turkey dry out overnight and you can pour off the liquid before roasting.
Happy Thanksgiving!
clay bishop
Hello, I have always used a oven bag to bake my turkey, in your recipe for dry brining a turkey you don’t mention anything about not using a oven bag to bake this turkey, so i am asking is it ok to use a oven bag after the turkey has been brined??? please let me know as soon as you can, thank you and happy holidays
Chef Dennis Littley
hi Clay
there really is no reason to use an oven bag but you can if you want to.
Happy Thanksgiving
Belen Slowey
Hello Chef,
I hosted Thanksgiving last year and followed your recipe to a T. Needless to say it was a big hit! so delicious and juicy! thank you so much for sharing. This year however, with the state of the world and all, its just my husband and I so we opted for a couple of turkey drumsticks & wings. I just want to ask what you recommend? I still would like to use the dry rub. will it work the same way? I am also debating roasting on air frying. I would greatly appreciate your opinion.
Thank you again for the BEST turkey recipe,
Happy Holidays,
Belen Slowey
Chef Dennis Littley
hi Belen
you can still use the dry rub on the turkey pieces, more as a seasoning than a brine (use less salt). I’ve never used an airfryer so I’m not sure what to tell you about cooking them that way, although I hear a lot of good things about air frying. Oven roasting is always a good option and you can even baste with seasoned butter to make them even tastier.
Happy Thanksgiving
Belen
Happy Thanksgiving chef Dennis and thank you for your reply! I did do the dry rub. I’m excited to see how these turn out. I will be roasting them in the oven but do highly recommend trying out an air fryer if you never have! I got the ninja one as a wedding present and it changed the way we make wings ( husbands favorite food) and even Cornell chicken! comes out perfectly crispy on the outside and juicy on the inside.
Thank you again and happy Thanksgiving!!
Christine
I have a 6 pound breast. Should I use 1 tablespoon of salt?
Chef Dennis Littley
yes as long as its Kosher or coarse sea salt. If it’s fine grain use 1 teaspoon
Christine
Thank yoh
Yasmine
Hi Chef Dennis. I have a turkey that seems to have been pre brined as it states it contains up to 8% of a solution of turkey broth/salt etc. I didn’t do the dry brine because of this but I would like to follow your seasoning and roasting method. Can I preseason it from now and just use less salt? How much should I use and how long should I roast an 11 lb turkey? Thanks so much in advance.
Chef Dennis Littley
you sure can. Just make the seasoning mix without the salt and use it as a dry rub. Following the roasting techniques will also help.
Roast for 30 minutes inverted at 425, and 1.5 – 2 hours at 325.
Stefani
Hi Dennis! I started my dry brine early Tuesday morning on my 20 lb organic turkey. There is about one inch of juices in the pan my turkey is in, and I’m concerned about them not reabsorbing into the turkey. Help! Thank you!
Chef Dennis Littley
hi Stefani
that is normal. Don’t save the juice, discard it.
Michael W
I have a 13 lbs turkey that is spatchcock turkey dry brined 4 day will be roasting in the oven
Can you recommend a temp an time
Chef Dennis Littley
start at 425 for 15 minutes then reduce to 325, you’re probably looking at 60-75 minutes.
Michael
Thanks
Tom S
I have a 22 pound turkey. I only have 24 hours to dry brine. I used 3 tbsp of fine grain salt and the suggested amount of the other herbs. I rubbed the brine mix under the skin and all over the skin. Will this make my turkey too salty?
Chef Dennis Littley
since you used the wrong salt, its going to be salty. You won’t get much benefit from the brine since, but you will get some benefit from the seasoning.
Kate
How long do you suggest for 35 lbs?
Chef Dennis Littley
45 minutes at 425 degrees and approximately 4-5 hours at 325 degrees.
Sandra Alvarado
I’m ready to roast.. do I cover the turkey? I’m going to start upside down for 45 min but not sure if I should cover it? My roasting pan comes w a cover.
Thanks!
I love your recipe!
Chef Dennis Littley
no cover is necessary
Happy Thanksgiving
Fawn
God Bless you for being online answering panicked questions the day before Thanksgiving! Thank you so much.
Fawn
Hi again,
I am also very nervous about it being opened so early. I have it wrapped tightly in a roasting pan and it’s still in it’s cut open vacuum seal bag with the juices. I opened it Monday evening. I am getting super worried about it going bad and wondering if I should just roast it today and reheat tomorrow!! Ugh… first thanksgiving fail!!!
Thank you!
Fawn
Good Morning Chef Dennis!
I am hoping you can give me a bit of guidance. I had planned to use your recipe exactly. I had my turkey ordered from the butcher, my brine all made and ready. I opened up my turkey on Monday night and realized it had been smoked. I had ordered a “tumbled” turkey. Apparently it’s smoked and tenderized “injected” ugh… but not cooked. I called the butcher and he said no need to brine or prepare it. Just season the skin before I cook it. Their instructions call for covering in foil and roasting 10-12 minutes per pound at 325. My turkey is 19 lbs. I would love to still follow your roasting instructions. Would you recommend that I should still pat dry, uncover and let it sit in fridge uncovered? Do you think I can just season the top (I saved the brine mix so I suppose I could sprinkle that on top) and still follow your melted butter, upside down and flip steps?
Thank you for any guidance. This is my first turkey!! Next time I guess I need to ask for more details on what turkey I’m ordering ;-).
Thank you and have a wonderful Thanksgiving!
Chef Dennis Littley
If you want to season it, you can use the ingredients I listed ( or add your favorites) just leave out the salt. Other than that you should be able to roast it per my listed instructions, as long as the butcher verified its not cooked.
Happy Thanksgiving