Ingredients

• 200g/7oz plain chocolate
• 200g/7oz white chocolate
• 225ml/8fl oz double cream
• 450g/1lb unsalted butter
• softened
• 450g/1lb caster sugar
• 8 free-range eggs
• 450g/1lb self-raising flour
• 200g/7oz plain chocolate (minimum 70% cocoa solids)
• melted
• 225g/8oz unsalted butter
• softened
• 450g/1lb icing sugar
• 200g/7oz plain chocolate
• melted
• 2 tbsp milk
• 450ml/16fl oz whipping cream
• 175g/6oz plain chocolate
• melted
• plus extra chocolate curls
• 225g/8oz white chocolate
• melted
• plus extra chocolate curls

Directions

• For the truffles
• melt 115g/4oz of the plain chocolate and 115g/4oz of the white chocolate in separate bowls.
• Meanwhile
• heat the cream until just boiling. Divide the cream between the plain chocolate and white chocolate and whisk each mixture until thick and glossy.
• Leave to chill in the fridge for 2-3 hours.
• To make the truffles
• melt the remaining plain chocolate and white chocolate in separate bowls. Line a baking tray with greaseproof paper.
• Scoop out two teaspoons of the white chocolate truffle mixture
• roll into a ball
• carefully dip into the melted plain chocolate and set aside on the baking tray. Repeat with the remaining white chocolate truffle mixture.
• Repeat Step 5 with the plain chocolate truffle mixture and dip the truffles into the melted white chocolate.
• Meanwhile
• for the marble cake
• preheat the oven to 180C/350F/Gas 4. Grease and flour two 15cm/6in sandwich tins and two 20cm/8in tins.
• Beat the butter
• sugar and eggs together in a large bowl until well combined. Fold in the flour.
• Divide the mixture between the four tins
• then pour a little melted chocolate into each tin. Swirl the cake mixture with a skewer to create a marbled effect.
• Bake the 15cm/6in cakes for 30-40 minutes and the 20cm/8in cakes for 40-50 minutes
• or until a skewer inserted into the middle of each cake comes out clean. Remove the cakes from the oven and set aside to cool completely.
• Meanwhile
• for the buttercream
• beat the butter and icing sugar together in a bowl until light and fluffy. Beat in the melted chocolate and milk. Set aside.
• For the chocolate ganache
• whisk 175ml/6fl oz of the whipping cream into the melted plain chocolate until smooth and glossy.
• Whisk the remaining whipping cream into the white chocolate until smooth and glossy.
• To assemble the cakes
• cut each 15cm/6in cake in half horizontally and fill with buttercream to make a four layer cake. Spread a little buttercream onto the 15cm/6in cake board and place the cakes onto them.
• Repeat Step 14 with the 20cm/8in cake.
• Ice the 15cm/6in cake with the plain chocolate ganache and the 20cm/8in cake with the white chocolate ganache. Chill in the fridge for 1-2 hours
• or until the ganache has hardened.
• To stack the cakes
• hold a dowelling rod at the side of the 20cm/8in cake and mark with a pencil where the icing comes to. Cut the rod and three others to the same length. Push the rods into the cake about 5cm/2in away from the sides
• to form the four corners of a square in the centre of the cake and top with the 15cm/6in cake.
• Decorate with the chocolate truffles and chocolate shavings.