Here's the recipe:
450g unsalted butter
450g light brown sugar
450g self raising flour
2.5 teaspoons mixed spice
4 overripe mashed bananas
For the frosting:
150g full fat cream cheese
150g smooth peanut butter
200g icing sugar, plus a little more for dusting
3 tablespoons of caramel sauce (optional)
handful of chopped peanuts (optional)
This recipe makes a very substantial cake - you can reduce the height of it by making less sponge:
325g unsalted butter
325g light brown sugar
325g self raising flour
1.5 teaspoons mixed spice
3 overripe mashed bananas
Use the same amount of frosting as you're covering the same surface area. Besides, it's so tasty you won't want to skimp on it
Grease and line three x 8 inch round tins and preheat your oven to 160 degrees C/Gas Mark 3
Cream the butter and sugar together until light and fluffy, then add the eggs one by one
Sift the flour and mixed spice together, then gently fold this into the mix. Lastly, add in the mashed banana
Divide the mixture equally between the three tins and smooth with the back of a spoon
Bake for about 40 minutes (about 30 minutes if you're using the smaller amount of sponge) until a skewer inserted into the centre of the cakes comes out clean.
While the cakes are cooling, make the frosting by beating together the cream cheese and the peanut butter until light and fluffy, then add gradually add the icing sugar.
Spread the top of two cakes with the frosting, the caramel sauce (if using) and a scattering of chopped peanuts (if using). Stack the cakes and dust the top and sides with icing sugar. You can decorate the top by piping on leftover frosting and adding the last of the chopped peanuts.
Note to cake decorators: this sponge is firm enough to level, cut and ice - just substitute the cream cheese for a butter icing or ganache that doesn't need to be refrigerated.