Preheat the oven to 375 degrees F. Line a standard muffin tin with cupcake liners. Set aside.
Whisk together the flour, baking powder, baking soda, and salt in a medium mixing bowl. Set aside.
To a large mixing bowl, add the brown sugar and butter. Using a hand mixer, beat for 1 minute. Add the eggs and vanilla and mix until well combined, scraping the sides of the bowl as needed.
Add the dry ingredients to the wet ingredients along with the applesauce and bananas. Beat until the banana is broken up with some tiny chunks. Stir in the chocolate chips with a rubber spatula or wooden spoon.
Using a cookie scoop or spoon, portion the muffin batter into the lined muffin tin. Fill each cup about 2/3 full. Bake for 20-22 minutes or until golden brown and the muffins spring back easily with a light touch.
Remove from the oven and let cool in the pan for a few minutes. Then carefully transfer the muffins to a wire rack to cool completely.
Notes
If desired, you can stir in 1/2 cup of shredded sweetened coconut along with the chocolate chips.
To make the chocolate chips stand out, add a few to the top of each muffin before baking. You can use mini chocolate chips or standard-sized ones for topping.