Rich and sweet with chocolate chips and walnuts, this banana loaf cake is made with butter and 2 tablespoons of mayonnaise, which is the secret to keeping it very moist. This recipe makes 2 loaf cakes.
Preheat oven to 180 C / Gas 4. Lightly grease and flour two loaf tins.
In a large bowl, cream together the butter and sugar until light and fluffy. Stir in the eggs one at a time, beating well with each addition. Stir in the mayonnaise and bananas. Stir together the flour, salt, baking powder and bicarbonate of soda. Blend the flour mixture into the banana mixture; stir just enough to evenly combine. Fold in the chocolate chips and walnuts. Distribute the mixture evenly between the two loaf tins.
Bake in preheated oven until a skewer inserted into the centre of the loaves comes out clean, about 50 to 75 minutes. Cool loaves in their tins for 20 minutes before removing to a wire rack to cool completely.