Preheat oven to 350F. Spray a four-section mini pan 6X3X2" or a larger 9x5x3" loaf pan with cooking spray.
Whisk together the flour, cocoa, baking soda, baking powder, salt, and cinnamon in a large bowl. Carefully add the chocolate chips.
In a large bowl of a standup mixer with a whisk attachment mix the eggs, oil, sugars, and vanilla extract until well blended. Remove from the mixer and fold in the zucchini and then the flour mixture, stirring just until combined.
Pour the batter into the prepared pans and bake for 55-65 for the large loaf pan or 40-45 for the smaller ones.
Checking with a toothpick inserted to come out clean. Let cool for 10 min. on a rack and then let cool completely out of the pan.
The bread keeps well for days in plastic wrap or can be frozen.