Preheat your oven to 350°F (175°C). Line an 8x8-inch pan with parchment paper or grease it lightly.
In a large bowl, mash the bananas until smooth.
Stir in the peanut butter, honey, vanilla, cinnamon, and salt. Mix well.
Add the oats and any optional mix-ins. Stir until fully combined.
Spread the mixture evenly into the prepared pan.
Bake for 25–28 minutes or until the top is golden and set.
Let them cool in the pan before slicing into bars. Store leftovers in an airtight container.