Heat oven to 160 °C fan. Grease and line a loaf tin.
Cream together butter and sugar until light and fluffy.
Beat 2 large eggs and mix into the butter and sugar mixture.
In a separate bowl, mix flour, baking powder, and bananas. Then fold in to the rest.
optionally, add a bunch of chocolate chips into the batter or sprinkle over the top once it's in the tin. Or, loosely mix in a couple of tablespoons of nutella or similar spread for a marble effect.
Pour into the prepared tin and bake until cooked through. (original recipe rec's 50 min)
Cool in the tin for 10 min, then move to a cooling rack.
Notes
If using nutella/etc, melt slightly and allow to cool before marbling in.
Original recipe recs some kind of watery icing and banana chips on top but i don't care for it