Chocka mocha layer cake with whipped caramel & mascarpone cream

MAKES 1 X 19CM CAKE CAKE 200g butter cut into small pieces plus extra for the tin 200g dark chocolate about 70 per cent cocoa 1 tbsp good-quality instant coffee mixed with 120ml water 3 medium eggs 2 tbsp buttermilk 100g self-raising flour 100g plain flour ¼ tsp bicarbonate of soda 300g golden caster sugar 25g cocoa powder ● Butter and line the base of a spring-form cake tin measuring about 19cm diameter x 7cm deep. Preheat the oven to 160C/140C fan/gas 3. ● Break the chocolate into a pan and add the butter. Pour in the instant coffee mixture and warm through over a low heat until just melted and combined. Beat the eggs in a bowl until slightly thickened, then stir in the buttermilk. Sift the flours, bicarbonate of soda, sugar and cocoa into a large mixing bowl. ● Pour the melted chocolate mixture from the pan into the flour mixture, followed by the egg mixture, and stir until everything is mixed and smooth. Pour into the prepared tin and bake for 1½ hours or until a skewer inserted comes out clean. Leave to cool in the tin, then turn out on to a wire rack to cool completely. Cut the sponge horizontally into three discs. ● For the caramel, melt the caster sugar gently in CARAMEL CREAM 150g golden caster sugar 75g soft light brown sugar 70g butter 375ml double cream 1 tsp vanilla extract 1 tbsp Kahlua or other coffee liqueur 250ml mascarpone a small pan until it starts to caramelise, then leave a little longer until it starts to turn a ruby red colour, taking care not to let it burn. Remove from the heat, whisk in the brown sugar and butter, then 75ml of the cream in a thin stream. Return to the heat and bring to a foamy boil for about 5 minutes, whisking occasionally until combined and smooth with all the sugar dissolved. Remove from the heat and set aside to cool completely. ● When ready to assemble the cake, whip the remaining 300ml double cream with the vanilla extract and liqueur to soft peaks, then fold in the mascarpone and the cooled caramel. Spread each layer with caramel cream and sandwich together. OPTIONAL FINISHES If wished, decorate with a dusting of cocoa or grated chocolate. You could also make some extra caramel, gently warm it and drizzle it over the top, allowing it to trickle down the sides.