1. In a bowl, combine the flour and baking powder.
2. Next, combine the banana, milk, and egg. Beat until the cake dough has formed.
3. Add the blueberries and stir with a spoon or spatula.
4. Pour the mixture into a previously oiled mold.
5. Place the mold in the air fryer for 15 minutes at 180 degrees Celsius.
6. Allow it to rest at room temperature.