- 200 g unsalted butter, plus extra for greasing
- 2 tbsp Fairtrade instant coffee
- 200 g Fairtrade golden caster sugar
- 4 medium free-range eggs
- 200 g self-raising flour
- 1 tsp baking powder
- 100 g walnut halves, roughly chopped
For the buttercream icing:
- 2 tsp Fairtrade instant coffee
- 150 g unsalted butter
- 300 g icing sugar, sifted
Preheat the oven to 180°C, fan 160°C, gas 4. Grease 2 x 20cm round cake tins and line with baking parchment. Dissolve the coffee granules in 1 tablespoon boiling water and allow to cool for 10 minutes.
Meanwhile, beat together the butter and sugar until light and fluffy, then add the eggs, one at a time, beating well after each addition. Using a large spoon, fold in the flour and baking powder. Stir in 50g of walnuts and the dissolved coffee.
Divide the mixture between the 2 cake tins and bake for 20-25 minutes, until golden and springy to the touch. Remove the cakes from the tins and leave to cool for 10 minutes on a wire rack.
To make the buttercream: dissolve the coffee granules in 1 teaspoon boiling water. Beat together the butter and icing sugar until pale and fluffy. Stir in the coffee and mix until well combined. Use half the buttercream icing to sandwich the cakes together. Cover the top with the remaining icing and decorate with the remaining walnuts.
Cook's tip: make sure the cakes are completely cool before icing, and use a pastry brush to gently sweep off any crumbs.