Before you start - preheat the oven at 200C/180C fan/gas 6.
Get a large bowl and mash the bananas with a fork (or a masher) - doesn't have to be silky smooth, leave it a little lumpy!
Then add the oil, the vanilla extract, and the sugar and mix this well.
To this mixture add the flour, the baking power and cinnamon and mix it well.
Last step - add the nuts to the mix!
Grease a loaf tin and pour the mixture into the tin.
Put the tin in the oven and bake it for roughly 20 min - it will be somewhat golden brown already by that point.
Open the oven up and cover the tin with tin foil (aluminium foil) - be careful it's hot!
Bake it for another 20 minutes and check how it's going - Poke with a knife to see make sure it's not wet inside.
For a more moist cake, leave the cake in its tin and cover in the foil for several hours (or even overnight)

3 or 4 very ripe bananas (depending on the size)
75ml vegetable oil
100 grams brown or cane sugar
225 grams plain flour
3 tsp of some sort of baking powder (2 if you are using self-raising flour)
3 tsp of cinnamon
1 tsp of vanilla extract
50 grams (a good hand full) of smashed walnuts (pecan nuts will also do)