Wash the mushrooms with a damp towel and pat dry. Snap off the stems and set the stems aside. Arrange the mushroom caps upside down in the prepared pan.
Trim off the ends of the stems. Chop the stems and place them in a bowl. Add the bread crumbs, cheese, garlic, parsley, salt and pepper to taste. Stir in the oil.
Spoon the crumb mixture into the mushroom caps.
Bake the mushrooms 18-20 minutes, or until tender.