Preheat your oven to 350°F (175°C) to ensure your Peanut Butter Banana Bars bake evenly.
Grease your baking pan or line it with parchment paper for easy removal later.
In a large mixing bowl, combine the mashed banana, creamy peanut butter, honey, vanilla extract, and light brown sugar. Whisk until well combined and smooth.
Crack in the large egg and mix until fully incorporated into the wet ingredients.
Sprinkle in the salt, baking soda, and baking powder. Then, add the oat flour and mix until just combined.
Gently fold in the peanut butter baking chips or chocolate chips.
Pour the batter into the prepared baking pan and spread it out evenly. Bake for about 20-25 minutes or until a toothpick inserted into the center comes out clean.
Once baked, let the bars cool in the pan for about 10-15 minutes, then transfer to a wire rack to cool completely before cutting.