Coconut Cake Supreme

I love this cake, especially since it's so easy and can be made ahead of time and chilled until ready to serve.

Coconut Cake Supreme

1 (18 1/4 oz.) yellow cake mix
2 cups sour cream or plain yogurt
2 cups sugar
1 1/2 cups flaked coconut
1 (8 oz.) carton Cool Whip, thawed

Prepare and bake cake according to package directions in two 9-inch round cake pans. Cool in pans 10 minutes before removing to wire rack to cool completely. For filling, combine sour cream and sugar. Mix well. Stir in coconut (filling will be soft). Set aside 1 cup of filling for frosting. To assemble, split cake into two horizontal layers. Place one layer on serving platter; cover with a third of the filling. Repeat layers. Fold reserved filling into thawed Cool Whip. Frost the cake with this mixture. Refrigerate for at least 4 hours before serving.
Makes about 10-12 servings.