100 g slightly salted butter, softened
200 g crunchy peanut butter
250 g light muscovado sugar
3 large eggs
250 g very ripe, black bananas mashed weight (see tip, below)
125 g natural yoghurt
1 tsp vanilla extract
250 g self-raising flour
1 tsp baking powder
2 tsp cinnamon
1 tsp ground nutmeg
A small handful peanuts, chopped, to garnish
300 g slightly salted butter, softened
75 g smooth peanut butter
650 g icing sugar, sifted
2 tsp vanilla bean paste
3 tbsp milk
- Heat the oven to 180°C, and butter 3 × 18cm cake tins, then line their bases with circles of baking paper. Beat the butter, peanut butter and sugar together with 1 egg until pale and light. Mix the mashed banana, remaining eggs, yoghurt and vanilla together, then pour into the peanut butter mixture followed by the flour, baking powder and spices. Combine to a smooth batter, then divide equally between the tins – weighing the mixture will give you even layers. Bake on the middle shelf for 25-30 minutes – a skewer poked into the centre should come out clean when the cakes are done. Cool in the tins for 10 minutes, then turn out onto wire racks to cool completely.
- For the frosting, mash the butter and peanut butter together in a big bowl. Mash in the icing sugar a little with a spatula (saves mess!), then swap to an electric whisk to beat the icing until smooth. Add the vanilla paste and milk and beat again.
- To assemble the cake, use about a quarter of the frosting to sandwich the sponges together on a cake plate or stand. Use a long palette knife to spread a little more of the icing over the entire cake in a very thin covering – but filling in any gaps between layers, and using the knife to create a smooth surface. Now put your cake in the fridge for 30-40 minutes until the icing is firm – this ‘crumb coating’ makes it easier to ice neatly.
- Once the icing is chilled and firm, cover the cake with the rest of the icing, again using a palette knife to give a clean, flat finish. Leave to set – finishing with a few more chopped nuts if you like.