Preheat oven to 350 and spray a muffin pan with non-stick spray.
To a small mixing bowl, add all your dry ingredients and stir them together (oat flour, baking powder, baking soda, cinnamon, nutmeg and salt).
To a large mixing bowl, add your butter/coconut oil, banana, applesauce, milk, vanilla and eggs and blend them together with a hand mixer.
Pour your dry ingredients into your wet ingredients and stir them together till you have a smooth, even batter.
Add your zucchini and chocolate chips to your batter and stir until well incorporated. Fill each muffin cavity with batter about 2/3 way full.
Bake in the oven for 18-20 minutes, or till the tops are springy to touch and a toothpick inserted comes out clean.
I would recommend storing these muffins in the fridge (in an airtight container) and they'll last about a week. These muffins are also freezer friendly!