2 (8 oz.) pkg. frozen coconut
1 pkg. Duncan Hines butter cake mix
1 1/2 c. Cool Whip
1 (8 oz.) box sour cream
2 c. sugar

Prepare cake mix according to directions, making three layers.

Bake as directed. Mix coconut, sugar and sour cream. Reserve one cup of mixture for later. Spread between layers. Add Cool Whip with the cup of the coconut mixture that you saved. Spread on top and sides of cake. Cover tightly and store in refrigerator for 3 days before serving.