River Cottage

Preheat the oven to 180C/Gas mark 4.

Sift the flour and baking powder together and set aside.

In a large mixing bowl, using either a wooden spoon or a hand-held electric whisk, beat the butter to a cream. Add the brown and caster sugars and beat until light and creamy. Add the eggs, one at a time, adding 1 tbsp flour with each and beating thoroughly before adding the next. Stir in the coffee essence. Now carefully fold in the remaining flour, half at a time, with a large metal spoon. Fold in the chopped walnuts, and sufficient milk to give a soft dropping consistency.

Spoon the mixture into the prepared tins, spreading it out evenly with the back of the spoon. Bake in the oven for 25-30 minutes until the tops are a light golden brown and the cakes spring back into shape when gently pressed. Leave in the tins for 10 minutes before turning out to cool on a wire rack.

Meanwhile, prepare the buttercream. Beat the butter to a cream, add the icing sugar and the coffee essence and beat until light and creamy.

To make glacé icing for the topping, sift the icing sugar into the bowl, add the coffee essence and 1-2 tbsp boiling water, and mix until thick.

Spread one of the cooled cakes with the buttercream. Sandwich together with the second cake and cover the top with the glacé icing. Finish with the chopped walnuts. 

This cake will keep for a week in an airtight tin.