1. Combine flour, sugar, baking powder and a little bit of salt in a large mixing bowl.
2. Whisk milk and egg into the flour mixture until no clumps remain in the resulting batter.
3. Add mashed bananas and mix well.
4. Add some butter to a medium warm frying pan.
5. Make smaller or bigger pancakes, up to you. Wait until tiny air bubbles form on top (2 to 5 minutes), turn and continue frying until the bottom is browned. Repeat.
Either eat the pancakes as they get ready or put a plate in a preheated oven (low degree) to keep the ready pancakes warm.