Hazelnut mocha cake

Preheat the oven to 180°C/160°C fan/gas mark 4. Grease three 16cm round cake tins and line the bases with buttered baking paper.

Whizz 75g of the hazelnuts (100 g)in a food processor until finely ground. Roughly chop the remainder and set aside. Dissolve the instant coffee (3 tsp) in 1-2 tsp boiling water.

Cream the butter (175 g) and caster sugar (250 g) together in a freestanding mixer until really pale and light, around 3-4 minutes. Add the eggs (3) and coffee in three batches, mixing well between each addition and scraping down the sides with a spatula.

Sift the flour (250 g), baking powder (2 tsp), bicarbonate of soda (1 tsp) and a pinch of salt into the bowl. Add the ground hazelnuts and soured cream (100 g) and mix again. Fold in the chocolate (75 g) and divide the mixture evenly between the prepared cake tins. Spread level using a palette knife and bake on the middle shelf of the preheated oven for about 25-30 minutes, until golden brown and well risen, and a skewer inserted into the middle of the cakes comes out clean. Leave to cool.

To make the icing, dissolve the remaining instant coffee (2 tsp) in 2 tsp of water. Add the butter (175 g) to a stand mixer and mix until light and fluffy. Gradually tip in the icing sugar (350 g) followed by the coffee.

Place one cake layer on a serving plate and spread a third of the coffee icing over the top. Add the second layer and another third of the icing, then finish with the final cake and remaining icing. Scatter over the reserved chopped hazelnuts and grated chocolate to serve.