Break cake into bite-sized pieces (about 8 cups). Arrange half of the cake pieces in bottom of 13 x 9 x 2 inch baking Pyrex dish. Top with half of the drained pineapple and cherries. Spread 1/2 of the Cool Whip over fruit and top with 1/2 of the coconut. Repeat layers ending with Cool Whip and coconut. Cover and refrigerate over night.
Cajun Country -- New Iberia, Louisiana