Preheat oven to 350F degrees.
Prepare a baking sheet with a non-stick baking mat or parchment paper.
Combine the banana, peanut butter, and Oatmilk in a large bowl and beat with electric beaters until smooth or combine with the paddle attachment of a stand mixer.
Add the whole wheat flour, baking powder, cinnamon, and salt and fold together until just combined with a spatula. Fold in your chosen mix-ins.
Refrigerate the dough for 20 minutes to allow it to become more firm.
Drop the dough (it will be sticky) into about 8 equal spoonfuls onto the baking sheet. Slightly press the mounds down so they are flat and top with the banana chip.
Bake for 12-15 minutes or until golden on the top and darker golden on the bottom. Remove from oven and allow to cool.