1 box butter flavored cake mix
2 c. sugar
1 (16 oz.) container sour cream
1 (12 oz.) pkg. frozen coconut, thawed
1 1/2 c. Cool Whip

Prepare cake mix according to package, making 2 thick layers. When completely cool, split both layers to make 4 layers. Combine sugar, sour cream, and coconut. Mix well and chill. Reserve 1 cup of this mixture for frosting. Spread the remainder between layers. Combine the cup of reserved mixture and the Cool Whip. Cover top and side of cake with this. Seal cake in a tight container and let set 3 days in the refrigerator before you cut it.