1/2 cup butter, softened
1 cup white sugar
1 egg
1 teaspoon vanilla extract
1 (18.25 ounce) package white cake mix
1 (12 ounce) container frozen whipped topping, thawed
1 (16 ounce) package flaked coconut
1/2 cup chopped walnuts
Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13 inch pan.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the egg and vanilla. Combine the cake mix and coconut, stir into the creamed mixture. Fold in the nuts. Spread evenly into the prepared pan.
Bake for 25 to 30 minutes in the preheated oven, until a toothpick inserted comes out clean. Let cool in the pan for 5 minutes before removing from the pan. Cool completely before frosting.