Preheat your oven to 350 F. Lightly spray a 10" bundt cake pan and set aside.
In your food processor with the shredder attachment, shred your zucchini and set aside.
In a medium bowl combine flour, cocoa powder, baking powder, baking soda, salt, and cinnamon.
In a separate bowl, whisk together oil and both sugars. Add flax eggs, milk, and vanilla extract. Stir to combine. Fold in shredded zucchini.
Add the dry ingredients to wet and mix until the dry ingredients are fully incorporated. Fold in chocolate chips and hazelnuts.
Pour batter into the prepared bundt pan and bake for 45-50 minutes until a knife inserted in the middle come out clean.
Remove from oven and let cake cool for 20 minutes before flipping it out onto a wire cooling rack to let cool all the way.