dressings / sauces | serves 16-18

You don’t use all the caramel, but it keeps in the fridge for a few days.

1. Start with the salted caramel. You can make this up to 2 days in advance. Place the sugar in a large saucepan with 50ml water. Gently heat on low, swirling the pan but not stirring, until just melted. (Don’t let children do this.) Turn up the heat a little and simmer gently, swirling regularly, until you have a clear, very dark golden caramel. Remove the pan from the heat then carefully and quickly whisk in the cream and butter. It will splutter a bit, but don’t worry about that. Keep whisking and beating until smooth, then beat in the salt. Let cool. If making the caramel in advance, keep it chilled but bring back to room temperature before using.
2. For the cake, preheat the oven to 150C/gas 2. Grease and line the bases of 2 round 23cm cake tins. Place the chocolate in a saucepan with the butter, coffee and a pinch of fine salt. Melt over a low heat until combined.
3. In a large mixing bowl, mix the flour, sugars and cocoa until well combined.
4. Beat the buttermilk into the melted chocolate mixture, then mix in the beaten eggs. Pour this mixture into the flour-sugar mixture and mix well. Spoon into the cake tins and bake for 75–90 minutes, until cooked through and a skewer inserted in the centre comes out clean. Cool the cakes in the tins for 10 minutes then turn onto a wire rack to cool completely.
5. Meanwhile, make the ganache. Place the chocolate in a bowl. Pour the double cream into a small pan and gently heat. Just before it starts bubbling, remove the cream from the heat and pour it over the chocolate (never add the chocolate to the cream or it will seize up). Leave the ganache to sit for a minute, then stir with a wooden spoon until completely combined. While the ganache is still slightly warm, evenly spoon one-third of it over one of the sponges and spread to the edge. Leave the rest of the ganache to cool completely at room temperature.
6. Meanwhile, place the unfrosted cake on a board or plate and drizzle with a few tablespoons of sea-salt caramel (you may need to warm it slightly before drizzling).
7. Using an electric mixer or whisk, beat the cooled ganache for 3–5 minutes, until light and fluffy. Spread over the salted caramel, top with the other sponge and finish with chocolate shavings, if you like.