Preheat oven to 350°F (175°C). Line an 8x8-inch baking dish with parchment paper.
In a large bowl, mash the bananas until smooth.
Stir in the peanut butter, honey, and vanilla extract until combined.
Add the oats, baking powder, cinnamon, and salt. Mix until a thick batter forms.
Fold in the chocolate chips if using.
Spread the mixture evenly into the prepared baking dish.
Bake for 25–30 minutes, or until the edges turn golden brown.
Let cool completely before cutting into bars.