Pre-heat your oven to 375 degrees.
Wash and dry your mushrooms.
Pop out the stems, chop and set both aside. You will need about 1/2 cup.
Add oil to a medium sauce pan.
Add your spinach and cook for about 2-4 minutes or until wilted.
Add in your garlic, chopped mushrooms stems and sauce for 5-6 minutes.
Add feta cheese and Italian bread crumbs.
Add onion powder, salt and pepper and set aside.
Stuff your bottom mushrooms with your mixture and add them to a greased baking dish.
Sprinkle with parmesan cheese.
Bake in the oven at 375 for 20 minutes.
Serving Size 1
* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.