1 stick unsalted butter, softened
1/2 c. vegetable oil
1 3/4 c. granulated sugar
2 lg. eggs
1/2 c. buttermilk
1 tsp. vanilla
1/4 c. cocoa powder
2 1/2 c. flour
1 tsp. baking soda
1/2 tsp. cinnamon
1/2 tsp. ground cloves
1/2 tsp. salt
2 c. grated well scrubbed zucchini
1 c. semi-sweet chocolate chips
3/4 c. chopped walnuts (optional)

FROSTING:

1 (8 oz.) pkg. cream cheese, softened
1 stick unsalted butter, softened
1 (1 lb.) box powdered sugar
1 tsp. vanilla
2 tbsp. cocoa powder

In a bowl with an electric mixer cream together the butter, the oil, and the sugar; beat in the eggs one at a time, mixing well after each addition. Add the buttermilk and the vanilla; mix well. Stir in the cocoa powder, the flour, the baking soda, the cinnamon, the cloves and salt until the mixture is combined. Fold in the zucchini, the chocolate chips, and, if desired, the chopped walnuts.

Pour the batter into 2 well greased 9 inch round cake pans or 9x13 and bake in a preheated 350 degree oven for 25 to 30 minutes or until cake tests clean. Let the cakes cool in the pans for 10 minutes, turn them out onto racks, and let them cool completely.

In a bowl with an electric mixer beat together the frosting ingredients until the mixture is smooth. Frost cake and refrigerate.