1 (18.5-ounce) box Duncan Hines Golden Cake Mix, baked according to package directions for 2 round layers
1 cup sugar
2 cups sour cream
2 (9-ounce) packages frozen coconut, thawed
1 ½ cups Cool Whip, thawed

Split each cooled cake layer in half, making 4 layers.

Combine sugar, sour cream and coconut. Chill. Reserve 1 cup sour cream mixture; spread remainder between layers of cake. Combine reserved sour cream mixture with Cool Whip. Blend until smooth. Spread on top and sides of cake. Store in airtight container in refrigerator for 3 days before serving.