Preheat the oven to 400 degrees. Coat a muffin pan with cooking spray.
Sift the flour, coconut powder, baking powder and salt together in a bowl.
Whisk together the eggs and sugar until creamy and lighter in color, about 1 minute. Add the buttermilk, oil, vanilla, mashed banana and 1/2 cup of peanut butter until creamy and thoroughly combined, about 2 minutes.
Slowly add the flour mixture to the liquid batter in thirds until just combined. Add 1/4 cup of chocolate chips and mix.
Spoon the batter equally into the muffin pan filling them to the top.
Heat the remaining 2 tablespoons of peanut butter in the microwave for 15-20 seconds, until warmed. Stir well.
For peanut butter swirl, spoon a little bit of warmed peanut butter on top of each muffin then use a toothpick to create swirls.
Divide the remaining 1/4 cup of chocolate chips to the top of each muffin.
Place into the oven and bake for 5 minutes. Reduce the heat to 350 degrees and continue to cook for 12-15 minutes, or until a tester inserted in the center comes out clean.
Remove from the oven and cool in the pan for a few minutes before putting them on a wire rack to finish cooling.
Serve plain or slathered with butter and lots of ice cold milk on the side. Enjoy.