Preheat the oven to 350. Spray silicone muffin tray with coconut oil OR place muffin liners inside the tray.
Prep your zucchini by grating it with a grater into a bowl. Then, take paper towels or cheesecloths and squeeze all the water out. Keep squeezing until you get it as dry as you can. You should end with about 1 cup of packed, dry, grated zucchini. (If you have a food scale, it should be around 166 grams.)
In a mixing bowl, combine all the dry ingredients together, stirring to avoid clumps.
Whisk the eggs, maple syrup, avocado oil and vanilla extract in a separate bowl. Add in the zucchini and mix until well combined, making sure to break up clumps.
Add the dry mixture to the wet and stir until well-combined. Add about half of the chocolate chunks to the batter, and save the other half to place on top of the muffins.
Pour batter into the muffin tray, evenly into each muffin. Top with the extra chocolate chunks. Bake on the center rack of the oven 18 to 22 minutes, or until muffins are cooked through.
Remove from oven. Allow muffins to cool at least 30 minutes before peeling and eating.
Store in airtight glass container in fridge.