1 box yellow cake mix
1 c. sour cream, light or no-fat if preferred
2 c. granulated sugar
2 c. flaked coconut
3 c. Cool Whip, light if preferred

Mix sour cream, sugar, and coconut together and refrigerate overnight. Bake cake in two 9 inch round cake pans. Cool. With a fork punch holes in the tops of the cake. Spread coconut mixture over top of bottom layer. Place top layer on bottom layer. Spread coconut mixture on top. Frost entire cake with Cool Whip. Sprinkle cake with additional coconut if desired. For best results, after frosting, refrigerate cake for at least 12 hours or overnight.