Preheat oven to 350°F.
In a medium bowl, whisk together dry ingredients.
In a large bowl, whisk together the remaining wet ingredients (except for the zucchini).
Add the dry ingredients into the large bowl of wet ingredients and mix well. Add zucchini to the batter and stir.
Place 12 large paper muffin cups into a standard-sized muffin tin. Use a spoon to pour batter evenly into all the cups. Optional: Place 1 walnut halve on top of each muffin.
Bake in the oven for 16-20 minutes, or until muffins feel springy and toothpick inserted comes out clean.
Let muffins cool for at least 10-15 minutes and enjoy!
Raw cacao powder is the same as cocoa powder but tends to be less processed and contains more nutrients, including iron, magnesium and antioxidants. If raw cacao powder is unavailable, unsweetened cocoa powder may also be used.
You can add walnut halves for garnish.