Heat oven to 350 degrees F. Grease 2 large bread loaf pans and set aside.
In a large bowl beat eggs until light and foamy. Add sugar, oil, zucchini and vanilla. Mix lightly, but well.
Add the flour, baking soda, baking powder, salt and cinnamon. Mix well until blended. Add nuts if you are using them.
Pour the mixture into the loaf pans and bake for 1 hour or until a toothpick inserted in the center comes out clean. Remove from oven and let cool 10 minutes. Remove from pans and drizzle with a powdered sugar and warm water glaze. Enjoy