Preheat oven to 350 degrees. Separate stem from mushroom, put aside.
In a bowl, mix together all ingredients except mushroom caps. Place about 1 teaspoon of mushroom mixture into each mushroom cap. If you have any leftover, evenly divide among caps.
Place mushroom caps on a cooking pan after filling, drizzle a little olive oil onto each mushroom cap, and top with a little more Parmesan cheese. Bake for 30-40 minutes or until golden brown and bubbly. You want the mushroom to get soft.