Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the rolled oats, mashed banana, chopped nuts, maple syrup, vanilla extract, cinnamon, baking powder, and salt. Mix well until all ingredients are evenly distributed.
Using your hands, form the mixture into small patties and place them on the prepared baking sheet.
Bake in the preheated oven for 25-30 minutes, or until the patties are golden brown and firm to the touch.
Allow the patties to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.