Preheat the oven to 350
Spray or muffin tin with non-stick spray or line with paper liners (normally I am a fan of skipping the liners, but with the chocolate chips getting “gooey”, this is one time that I use them!)
Combine flour, cocoa powder, baking soda, baking powder, salt, cinnamon and chocolate chips.
In a separate larger bowl, whisk together the eggs, oil, sugar and vanilla until combined.
Stir the grated zucchini in the to egg mixture.
Gradually add the dry mixture in to the wet mixture until combined. Do not overmix!
Fill muffin tins about ⅔ – ¾ full.
Bake for 22-25 minutes or until a toothpick inserted into the center comes out clean.
Allow to cool for a several minutes in pan before removing to a cooling rack.