Heat oven to 200C/180C fan/gas 6. Mash 3 large black peeled bananas with a fork, then mix well with 75g vegetable or sunflower oil and 100g brown sugar.
Add 225g plain flour, 3 heaped tsp baking powder and 3 tsp cinnamon or mixed spice, and combine well. Add 50g dried fruit or nuts, if using.
Bake in a greased, lined 2lb loaf tin for 20 minutes. Check and cover with foil if the cake is browning.
Bake for another 20 minutes, or until a skewer comes out clean.
Allow to cool a little before slicing. It's delicious freshly baked, but develops a lovely gooey quality the day after.