Preheat oven to 350 degrees F (180 C). Spray a 13 x 9 x 2-inch baking pan with nonstick cooking spray.
In a large bowl, combine sugar, margarine (or butter, if using) oil, vanilla and eggs. Beat well. Add flour, cocoa, baking soda, cinnamon and buttermilk. Blend well. Fold in zucchini, chocolate chips and nuts (nuts are optional). Pour into prepared pan. Bake for 35 to 40 minutes, or until a toothpick inserted in center comes out clean. Remove from oven, and cool in pan for 15 minutes before inverting and letting cake cool completely. When ready to serve, drizzle each slice with glaze.
Beat all ingredients until smooth. Drizzle over cake.
Makes 12 servings.
Date: August 14, 2003