Chocolate Zucchini Cake

1/2 c. margarine
1/2 c. oil
1 3/4 c. sugar
2 eggs
1 tsp. vanilla
1/2 c. sour milk (I just add 1/2 tsp lemon juice to regular milk)
2 1/2. flour
2 c. diced zuchinni
1/2 tsp. baking powder
1 tsp. soda
1/2 tsp. cinnamon
1/2 tsp. cloves
1 c. chocolate chips
1 c. nuts (optional)
3 Tbsp. cocoa

Beat well with mixer. Bake in 9x13 pan at 325 for 40-45 minutes. Needs no frosting! (But is good warm w/ cool whip).