First, preheat your oven to 350 degrees Fahrenheit.

Second, mash all of the bananas in a mixing bowl with either a fork or a potato masher.

Third, you will want to add the peanut butter to the mashed bananas and mix it all together very well with a mixing spoon or a hand mixer.

Next, divide half of the mixture into another mixing bowl.

After that, you will add the cocoa powder to just one mixing bowl and mix well.

At this point, you will need to add each bowl of batter to a muffin pan.

After that, place the muffin pan into the oven and bake for 18-20 minutes.

Lastly, take the muffins out and place them on a plate or a cooling rack and let them cool before serving.

Finally, you can serve and enjoy!