Preheat oven to Gas Mark 4/180°C/350°F and grease and line a loaf tin.
Mix together the dry ingredients (plain flour, wholemeal flour, baking powder, bicarbonate of soda, salt, spices, chopped nuts, oats, and chocolate if using) and set aside.
In a large bowl, whisk the eggs and stir in the sugar, melted butter or oil and milk. Add the dry ingredients to the egg mixture in 3 batches, alternating with the mashed bananas. Mix until just combined but be careful not to overmix.
Pour the batter into the prepared tin, and if you’re feeling fancy sprinkle the top with some more chopped nuts and brown sugar - it’ll caramelise into a lovely topping!
Bake for about 60 minutes or until a skewer inserted into the centre comes out clean.
Leave to cool in the tin for about 5 minutes, and then turn out onto a cooling rack to cool completely. If you can wait that long...