1.Preheat oven to moderate, 180°C. Lightly grease and line a 10cm x 20cm loaf pan, allowing baking paper to overhang 2cm on long sides.
2.In a bowl, using an electric mixer, beat butter and sugar together until pale and creamy. Add eggs one at a time, beating well after each addition. Beat in syrup.
3.Fold in banana, then add combined sifted flours and soda. Fold in half nuts.
4.Spoon into pan. Smooth surface. Sprinkle with remaining nuts.
5.Bake 55-60 minutes, until cooked when tested with a skewer. Cool in pan 5 minutes. Turn out onto a wire rack to cool completely. Serve in slices, with honey or butter.
You can replace maple syrup with honey, if preferred.