Mix the flour, baking powder, salt in a bowl and set aside
Mix the melted butter and sugar in a large bowl and beat until blended
Beat in the eggs one a time (don’t worry if the mixture curdles) and then stir in the mashed bananas, orange zest, chocolate and vanilla extract.
Then add the dry flour mixture. It is easier to add this in stages, stirring it in well between each addition.
Pour the mixture into your prepared loaf tin and bake in the middle of your pre-heated oven for 1 ¼ hours. You will know when it’s ready as if you insert a skewer into it, it should come out pretty clean.
Leave it in the tin to cool before slicing.