Preheat your oven to 375°F. Line your muffin tin with paper liners and set it aside. Prepping the tin early makes everything flow smoothly!

Peel the bananas and mash them thoroughly in a large mixing bowl. I use a fork, but a potato masher also works great.

Add the brown sugar, egg, applesauce, melted butter, and peanut butter to the mashed bananas. Mix until well blended and smooth. The mixture should look creamy and silky.

In a separate bowl, whisk together the whole wheat flour, all-purpose flour, cocoa powder, baking powder, baking soda, and salt. Dry ingredients need to be well combined to avoid uneven flavors or clumps.

Gradually add the dry mixture into the wet ingredients. Gently fold together using a spatula, being careful not to overmix. Muffin batter should be slightly lumpy for the best texture. Add chocolate chips and fold them in.

Spoon the batter into your prepared muffin tin, filling each liner about 2/3 of the way. If you want to, sprinkle extra chocolate chips on top for a pretty, melty finish.

Place your muffin tin in the preheated oven and bake for 20 minutes. To check doneness, insert a toothpick; it should come out with a few crumbs but no wet batter.

Remove muffins from the oven and transfer them to a wire rack to cool for about 10 minutes. Enjoy them warm or at room temperature with a coffee or tall glass of milk!