Chocolate Peanut Butter Banana Bread

0 Preheat oven to 325°F / 163°C.
1 Spray a loaf pan with nonstick cooking spray.
2 In a large mixing bowl, whisk together melted butter, mashed banana, and brown sugar until evenly combined (it will be slightly lumpy). Whisk in eggs and vanilla. 
3 In a second bowl, whisk together flour, peanut butter powder, baking soda, and salt. 
4 Pour dry ingredients over wet and stir just until no dry spots remain.
5 Stir chocolate chips into batter.
6 Pour batter into prepared loaf pan. Spoon peanut butter over the top of the batter. Using a knife, draw swirls through the peanut butter so that it blends into the batter. Scatter a few chocolate chips on top. 
7 Bake bread until the center is set, 60 to 70 minutes.
8 Allow to cool before slicing and serving.