Preheat the oven: Preheat your oven to 350°F (175°C). Line an 8x8 inch baking pan with parchment paper or lightly grease it for easy removal.
Mash the bananas: In a mixing bowl, mash the ripe bananas with a fork or potato masher until smooth.
Mix in the peanut butter: Add the peanut butter to the mashed bananas and stir until well combined.
Add oats and sweetener: Stir in the rolled oats and honey (or maple syrup) until the mixture is fully incorporated.
Transfer to baking pan: Pour the mixture into the prepared baking pan and spread it evenly using a spatula.
Bake: Place the pan in the oven and bake for 20 minutes or until the edges turn golden and the bars are set.
Cool and slice: Let the bars cool completely in the pan before slicing them into 9 squares. Enjoy!