1Heat oven to 350. Lightly spray a baking sheet w/ cooking spray. Remove stems from mushrooms, chop stems fine. Place mushroom on baking sheet.
2Spray a lg skillet w/ cooking spray. Place over medium heat. Cook mushroom stems, red bell pepper and scallions, stirring, for 2 mins. Stir in cream cheese, parsley, bread crumbs, garlic powder and pepper. Cook, stirring for 2 mins.
3Spoon mix evenly into mushroom caps. Spray mushrooms w/ cooking spray. Cover and bake 15 mins. Uncover, bake 5 mins more.