1. Turn your oven on to 180c/350f/gas mark 4.
2. Put the flour, sugar, baking soda, baking powder, and salt into a mixing bowl, and give them a quick mix with your hands (take your rings off first!).
3. Cut the butter into 18 cubes, and place in the mixing bowl. Use your fingers to mix these ingredients together, until you have something that resembles breadcrumbs.
4. Beat the eggs with the vanilla extract, and pour into the mixing bowl. Stir the mixture vigorously with a wooden spoon, until it resembles a thick porridge.
5. Stir in the raisins.
6. Peel the bananas, and place them into a bowl - ensuring any hard and stringy bits are removed. Mash with a fork, until they resemble a baby dinner.
7. Add the banana mash to the cake mixture, and stir vigorously with a wooden spoon.
8. Grease the loaf tin with a little butter (even if it is a non-stick loaf tin).
9. Pour the mixture into the loaf tin, and place in the oven for between 50 and 65 minutes (oven cooking times often vary a lot!).
10. You can check if your banana bread is properly baked, by sticking a knitting needle into it (well that's what my mum used, so that's what I use as well!). If any of the mixture sticks to the needle, it isn't ready.
A top tip ...If you don't like the odd burned bit around the top of your banana bread, split the mixture between two loaf tins.