Preheat the oven to 350 degrees F, and prepare a muffin pan by spraying nine of the cups with cooking spray. Set aside.
In a mixing bowl, stir together the mashed banana and the almond butter until smooth. Stir in the egg and remaining ingredients, ending with the zucchini. Stir in the chocolate chips.
Distribute the batter among the prepared muffin cups. Bake for 15-20 minutes, until the tops of your muffins are just set and a toothpick inserted into the middle comes out clean. (These take 18 minutes in my oven.) Allow the muffins to cool in pan for 10 minutes before removing. (It’s helpful to run a knife around the edges to loosen and gently pry the muffins out.) Store in an airtight container at room temperature for 3-5 days or up to a week in the fridge. These muffins freeze well, too.
*I prefer almond butter in this recipe for its relatively neutral flavor, although peanut butter would work, too. Sunflower seed butter could be used for those with a nut allergy. When nut and seed butters are stored in the refrigerator, it helps to bring them to room temperature before using to make them easier to stir into the batter.
**For quick and thorough moisture removal, I like to wring out the shredded zucchini in a clean tea towel (and then pull apart what becomes a clump) before stirring into the batter.
***The chocolate chips can be considered optional, although they make these muffins tastes especially brownie-like. For the most impact with the fewest chips, I often dot 6-8 chips over the muffins before baking instead of stirring the noted 1/4 cup into the batter. That way, you get a hint of chocolate in each bite with a modest amount of added calories and sugar.
Tip: For an accurate measurement of the cocoa powder, fluff it up, spoon into the measuring cup, and then level off with the straight edge of a knife—as is recommended when measuring all-purpose flour. Scooping into the powder compacts it, resulting in a greater amount being used, which can in turn lead to a less sweet end result, since cocoa powder is inherently bitter. Optionally, a kitchen scale allows for quick and easy measuring and spot-on accuracy.