Prep: 15 minutes Cook: 1 hour Serves: 8
Preheat the oven to 170 fan bake. Grease and line a standard loaf tin.
Beat the butter, sugars and vanilla together until very light and pale – at least 10 minutes. Add the eggs, one at a time, beating well between each addition.
Fold through the flour, baking powder and baking soda, then fold in the mashed banana.
Take out one third of the batter and place in a separate bowl and mix in the peanut butter. Add the chopped chocolate to the remaining 2⁄3.
Spread some of the chocolate chunk batter over the bottom of the loaf tin. Dollop some of the peanut butter mixture on top, then dollop some of the chocolate batter on top, repeating until no more batter is left.
Sprinkle over the raw sugar. Bake at 170 for 30 minutes, then reduce the oven temperature to 160 and bake a further 30 minutes, or until the loaf is cooked.
Recipe and photography by Abbey Macfie