Step 1

In a large bowl with mixer cream together sugar and butter; Add oil, flour, vanilla, buttermilk, cocoa, eggs and baking soda. Fold in zucchini, chocolate chips and nuts. Pour into a 13 x 9 inch baking dish that has been sprayed with cooking spray. Cook in preheated 350 degree oven 35 to 45 minutes until done in center.

Step 2

Mix together cocoa, butter, milk and vanilla with mixer. Add sugar, mix well. If too thick, add more milk. Spread over cooled cake.