Then add the layer of spinach (sauteed with the shallots). You can add bleu cheese crumbles or a cheese of your choice on top of the spinach for added flavor.
Next add the mushrooms, you’ll notice how dark they are. I let the mushrooms cook for about 15 minutes to allow them to caramelize to enhance the flavor.
The last step is to add the top layer of puff pastry dough. Brush the edges of the bottom layer with the lightly beaten egg, before adding the top layer.