Put butter in large micro proof mixing bowl and cook on HI for 45 seconds, or until melted. Blend in brown sugar and applesauce. Stir in all remaining ingredients until well blended. Pour into an 8 inch square micro proof baking dish, greased on bottom only. Cook on HI for 7 minutes. Rotate dish and cook on MEDIUM for 2 minutes, or until no longer doughy. Cool in pan. When cool, frost with