Microwave 2 Tbsp. margarine and 2-1/2 cups marshmalllows in medium microwaveable bowl sprayed with cooking spray on HIGH 2 min. or until margarine and marshmallows are melted and mixture is well blended, stirring after each minute. Add raspberry jelly powder; mix well. Stir in 3 cups cereal; press onto bottom of 9-inch square pan sprayed with cooking spray.