Coconut Cake Supreme

1 (18.25 ounce) box yellow cake mix
2 cups (16 ounces) sour cream
2 cups granulated sugar
1 1/2 cups flaked coconut
1 (8 ounce) carton frozen whipped topping, thawed
Fresh mint and red gumdrops (optional)

Prepare and bake cake according to package directions in two 9-inch round cake pans. Cool in pans for 10 minutes before removing to a 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 each cake into two horizontal layers. Place one layer on a serving platter; cover with a third of the filling. Repeat layers. Fold reserved filling into whipped topping; frost cake. Refrigerate for at least 4 hours. Garnish with mint and gumdrops, if desired.