heat oven to 180c or 160c fan or gas mark 4
butter the loaf tin and line it with greaseproof paper
cream the butter and sugar together until fluffy
add the vanilla, eggs and half of the flour and stir well
fold in the remaining flour and the baking powder
stir in the mashed banana
add the chocolate chips
pour into the tin
bake for 50 - 60 mins
check with a skewer and remove when cooked
allow to cook on a wire rack
enjoy