Preheat the oven to 350°F and line a 12-cup muffin tin with paper liners.
In a large bowl, whisk together 1½ cups all-purpose flour, 1 tsp baking powder, 1 tsp baking soda, 1 tsp ground cinnamon and ½ tsp salt.
In a separate medium bowl, whisk together 1 large egg and ½ cup brown sugar.
Mix until well combined.
Add and stir together 3 mashed ripe bananas, ½ cup creamy peanut butter and ¾ cup plain yogurt.
Mix until smooth.
Stir in 1 tsp vanilla extract.
Pour the wet ingredients into the flour mixture and stir gently until just combined. Do not overmix.
Fold in ½ cup chocolate chips, if using.
Divide the batter evenly among the 12 muffin cups, filling each about ¾ full.
Bake for 15–20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool in the pan for 10–15 minutes.
Transfer the muffins to a wire rack to cool completely.
Serve and enjoy!
Notes
When testing for the doneness of the muffins, make sure to not insert the toothpick into a chocolate chip in the muffins. Refrigerate any leftover muffins in an airtight container for up to 5-6 days.