Preheat an oven to 350ºF and spray a loaf pan with cooking spray before adding a sling of parchment paper across the length of the pan.

Mix the dry ingredients in one bowl and the wet ingredients in another. Once mixed, combine wet and dry ingredients, stirring everything together until evenly combined.

Add to the loaf pan and add small dollops of the remaining 2 tablespoons of peanut butter on top, using a toothpick to create a swirl. (I used natural peanut butter at room temperature. For thicker peanut butter, you may want to slightly heat or add a little oil to thin it out.)

Bake for 55-65 minutes until the banana bread has risen and slightly cracked in the center. A toothpick should come out clean from the center and toward the top of the loaf.

Let the banana bread cool in the pan for 20 minutes before removing from the pan and cooling on a wire rack. Let the loaf cool completely before slicing.