01 - Preheat the oven to 350°F and line an 8x8-inch baking pan with parchment paper.
02 - In a large mixing bowl, combine the mashed bananas, peanut butter, eggs, maple syrup, and vanilla extract. Mix until smooth and well incorporated.
03 - Add the cinnamon, salt, and baking soda to the wet mixture. Stir thoroughly to combine all ingredients evenly.
04 - Gently fold in the dark chocolate chips if using, distributing them throughout the batter.
05 - Pour the batter into the prepared baking pan and spread it evenly with a spatula.
06 - Bake for 20-22 minutes until the center is set and a toothpick inserted into the middle comes out clean.
07 - Allow to cool completely in the pan before slicing into 8 bars for serving.