1 pkg. butter flavored cake mix
2 c. sugar
1 (8 oz.) container sour cream
1 (12 oz.) pkg. coconut
1 (8 oz.) Cool Whip

Prepare cake mix according to directions on package, making two (8 or 9 inch) cake pans. Split cake after cooled, making 4 layers. Blend together sugar, sour cream, coconut, and 1 cup Cool Whip; chill. Spread all but 1 cup of sour cream mixture between layers. Blend the remaining cup of sour cream mixture with more Cool Whip and spread on top and sides of cake. Seal in an airtight container in refrigerator for 3 days before cutting. Store remainder in refrigerator.