I personally am the only one that loves this dish, I live with my youngest son and husband and the saying, "real men love quiche" does not mean my house. I am sharing because I think someone else will love it as much as I do.
Preheat the oven to 350 degrees. Grease a 9-inch pie plate with non-stick cooking spray.
In a medium skillet, heat the olive oil and then saute the fresh spinach leaves and sliced mushrooms for 4 to 6 minutes, or until the mushrooms have browned some and the spinach has "wilted".
In a mixing bowl, wisk the eggs with the feta cheese.
Place the pie crust into the prepared pie plate. Gently add the mushrooms and spinach. Then pour the egg mixture over the top.
Place the quiche in the preheated oven and cook for 30 minutes. Remove from the oven and add the shredded mozzarella cheese to the top. Return to the oven and bake for 5 to 10 minutes, or until the cheese has melted.
Serve with a side of fresh fruit or salad for breakfast, brunch, lunch or dinner.