These double chocolate zucchini muffins are a decadent morning treat. They're tender and moist, rich with chocolate flavor, and lightly spiced with cinnamon and nutmeg.
Preheat oven to 350 degrees Fahrenheit. Prepare a 12-cup muffin pan with spray oil.
In a large bowl, combine the flours, cocoa powder, sugar, baking soda, salt, baking powder, cinnamon and nutmeg. Stir with a whisk or fork until combined. Make a well in the center of the mixture then set aside.
In a separate bowl or large measuring cup, whisk together the milk, oil, eggs, and vanilla. Pour all at once into the well in the middle of the dry mixture. Add the shredded zucchini. Stir gently together just until all dry ingredients are incorporated. Do not overmix, but be sure dry ingredients at the bottom of the bowl have been mixed in.
Gently fold in the chocolate chips.
Spoon batter into the prepared muffin pan, filling each cup almost to the top. Bake for about 20 minutes, then check by touching the tops of the muffins with a fingertip. If they are slightly sticky, continue baking until they are no longer sticky and spring back lightly to touch (about 2-3 more minutes). Remove from oven and allow to rest in pan for 5-10 minutes before removing to rack to finish cooling.
Store completely cooled muffins in an airtight container at room temperature for 3-4 days.