Ingredients

• 100g/3½oz dark chocolate
• broken into pieces
• 30g/1oz unsalted butter
• 50g/1¾oz icing sugar
• 75ml/2½fl oz double cream
• 1 large free-range egg
• 3 large free-range egg yolks
• 1 tsp vanilla extract
• 150g/5½oz caster sugar
• 400ml/14fl oz double cream
• 75g/2½oz toasted skinless hazelnuts
• finely chopped
• 200g/7oz dark chocolate
• broken into pieces

Directions

• Double line a 900g/2lb loaf tin with cling film.
• For the ganache
• melt the chocolate and butter in a large heatproof bowl over a saucepan of simmering water (do not allow the bottom of the bowl to touch the water). Stir in the icing sugar and double cream. Set aside.
• Meanwhile
• place the egg
• egg yolks
• vanilla extract and sugar in a heatproof bowl and set it over a saucepan of simmering water
• making sure the bowl doesn’t touch the water. Beat the mixture over the heat for about 8 minutes using a hand-held electric whisk
• until it is thick and pale. Remove from the heat and set aside.
• In a separate large bowl
• whip the double cream until it is just stiff. Gently fold in the pale egg mixture until combined.
• Pour half the mix into the prepared loaf tin. Make a shallow well along the centre and pour in the ganache. Pour the rest of the semifreddo mix over the top and use a knife to make swirls with the ganache. Cover with cling film and place in the freezer to set for 6 hours.
• Just before serving
• melt the chocolate pieces in a bowl standing over a pan of simmering water (do not allow the bottom of the bowl to touch the water). Set aside to cool to room temperature.
• To serve
• turn the semifreddo out onto a serving platter and carefully remove the cling film. Pour the cooled chocolate over the top
• sprinkle with the toasted hazelnuts and serve in generous slices.