"These muffins are the softest, moistest, most delicious that I have ever had, and they're sugar free! They can even be turned paleo with a few substitutions. Seriously, they are so good that I created an Allrecipes account just to share them!"
Preheat oven to 350 degrees F (175 degrees C). Grease a 12-cup muffin tin with cooking spray.
Combine banana, butter, egg, and coconut oil in a bowl; mix until well combined. Add zucchini and vanilla extract; mix well.
Combine flour, baking soda, cinnamon, nutmeg, and salt in a separate bowl. Add gradually to zucchini mixture, stirring until well combined. Stir in milk slowly. Scoop 1/4 cup batter into each muffin cup. Sprinkle each muffin with 1 teaspoon brown sugar.
Bake in the preheated oven until tops spring back when lightly pressed, about 20 minutes.