Place the banana, egg, almond or peanut butter, honey, flaxseed, cocoa powder, vanilla, cinnamon, baking soda, and salt in a blender. Blend until smooth and frothy.
Mix the zucchini and chocolate chips in by hand.
Fill each muffin cup ¾-full with the batter.
Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
Let muffins completely cool in pan, and store in an air-tight container or resealable plastic bag for up to 5 days.