Mash the bananas in a bowl until mostly smooth - a few lumps are fine.
Beat in the eggs, then stir in the oats and cinnamon if using. Let the mixture sit for 2 minutes for the oats to absorb some moisture.
Heat the oil or butter in a non-stick frying pan over medium heat.
Spoon about 2 tablespoons of mixture per pancake into the pan. Cook for 2-3 minutes until the underside is golden, then flip carefully.
Cook for another 1-2 minutes until set and golden on both sides.
Serve stacked with a drizzle of honey or maple syrup.