In a skillet lightly sauté Spinach, olive oil and Mushrooms over low heat until spinach is wilted. Allow to cool.
In a mixing bowl add eggs with salt, pepper, red pepper flakes and Half & Half. Whisk gently for 1-2 minutes, until the mixture is a solid light yellow color.
Put the cooled spinach and mushroom into pie shell and top with Parmesan and Feta Cheese.