Beat eggs with a fork til foamy. Add oil, coffee, sugar, and vanilla, stir well. Mix dry ingredients in a separate bowl then add to liquids. Stir in zucchini and chocolate chips.
Grease 2 large bread pans. Pour batter in prepared pans and bake in preheated 350 degree oven for approximately 40 minutes. Test center with toothpick until it comes out clean. Cool in pan for about 20 minutes before removing. For muffins, bake in prepared tins for 18 to 22 minutes (check at 18 minutes if center is done with a toothpick)