Pre heat oven to 400.Saute onions, bell pepper, and garlic in oil. About 5 minutes. Add spinach. Wilt the leaves down for about a minute. Turn off heat set aside.

In a mixing bowl add egg, parmesan, and ricotta. Mix together. Add onion mix. Mix.

Take out stems and scoop out brown gills. Add salt pepper to the mushroom. Add scoops of mix to the mushrooms. Top with marinara and mozzarella. Spray sides and top of mushroom with oil.

Bake for 20 to 25 minutes. Enjoy