Preheat oven 350. Grease 9x13 pan. Prepare and bake brownies according to package directions. Remove from oven. Sprinkle marshmallows on hot brownies. Return to oven for about 3 mins. Place choc chips, peanut butter and margarine in medium saucepan. Cook on low, stirring constantly until chips are melted. Add rice cereal, mix well. Spread over marshmallow layer.
