Melt butter In a 13x9-inch pan. Sprinkle brown sugar over butter. Arrange the drained pineapple slices over the brown sugar. Place a cherry in the center of each slice.
Combine cake mix, piña colada, water and eggs, mixing according to package directions. Fold in coconut. Pour cake mixture over pineapple. Bake at 350° F for 40 minutes. Should be springy to touch. Invert immediately on a plate.
For topping: Beat together cream and pina colada. Serve over warm cake.Servings: