Preheat oven to 225 degrees Fahrenheit.
Mash the bananas.
Mix in the oats, cinnamon, and olive oil with a spoon. Stir until it starts to pull away from the bowl and is well blended.
Cover the bowl and let the dough rest for 5 minutes, allowing the oats to expand.
Roll out the dough and cut into shapes with cookie cutters.
Put the shapes on a flat cookie sheet.
Bake for 25 minutes, then flip them over and bake for another 20 minutes.
Let them thoroughly cool before sharing with your fur baby.