Melt 1 stick butter or margarine. Mix with 1 egg and 1 box cake mix. Pat in bottom and sides of a greased 9x13-inch pan. Beat 8-oz. pkg. cream cheese, eggs and 1 box powdered sugar and 1 t. vanilla. Pour mixture over bottom of dough. Bake at 350 degrees for 35 minutes. Dust top while warm with powdered sugar. Makes 6-8 servings.