Turn the oven on and heat to 180C
Grease the baking pan with some butter
Cream the butter and sugar in a bowl or electric mixer
Beat the egg in a small bowl then add the batter
Add the mashed bananas one at a time beating well
Mix in the flour a little at a time. Mix well
Add the baking powder and bicarbonate of soda. Mix well
Add two teaspoonfuls of milk. Mix well
Pour the mixture into the baking pan using the spatula to level the top
Bake for 30 min and check consistency with a skewer or knife. If they come out with cake mix coating them bake for another 15 min
When done leave to cool in the pan
Turn out and top with icing if you like