Preheat oven to 350 degrees. Clean mushrooms with damp paper towels. Remove stems.
Place mushrooms on a rack in a large broiler pan. Set aside. Fry sausage in skillet until brown. Crumble sausage, drain, and return to skillet. Stir in cream cheese and crushed red pepper. Spoon evenly into mushroom caps. Bake at 350 degrees for 15 minutes.