1. Preheat the oven to 170°C/325°F/gas 3.
2. Pour the bourbon into a small pan and add the sultanas and nutmeg. Heat gently for a few minutes before turning off the heat and allowing them to soak up the liquid.
3. Melt the butter and pour into a large mixing bowl. Add the brown sugar and mix well.
4. Crack in the eggs one at a time, beating well before adding the next.
5. Stir in the bananas and sultanas and sift over the flour, baking powder, bicarbonate of soda and salt.
6. Fold together until there are no traces of flour and pour into the lined loaf tin.
7. Bake in the oven on the middle shelf for 45 - 50 minutes, or until a skewer comes out clean.
8. Allow to cool in the tin before wrapping well and slicing whenever you fancy a sweet treat. The banana sultana cake is best eaten after a day, after it's had time to mature.