Heat the oven: Preheat to 350°F (175°C). Line a baking sheet with parchment paper.

Mash the bananas: In a medium bowl, mash the bananas until mostly smooth with just a few small lumps.

Stir in wet ingredients: Add the nut butter, maple syrup or honey, and vanilla. Mix until creamy and well combined.

Add oats: Fold in the rolled oats until the mixture is thick and evenly coated. If using, stir in cinnamon or a pinch of salt.

Adjust texture: The dough should be scoopable and hold shape. If it’s too loose, add a few more tablespoons of oats. If too stiff, splash in a teaspoon of milk or water.

Portion the cookies: Scoop heaping tablespoons onto the prepared sheet. Gently press each mound to about 1/2-inch thick; they won’t spread much in the oven.

Bake: Bake for 12–15 minutes, until the edges look set and lightly golden on the bottom.

Cool: Let them cool on the sheet for 5 minutes, then transfer to a rack. They firm up as they cool.