Ingredients

• 125g/4½oz dark chocolate
• 4 free-range eggs
• separated
• 125g/4½oz caster sugar
• plus extra for dusting
• 2 tbsp cocoa powder
• sifted
• 325g/11½oz icing sugar
• sifted
• 100g/3½oz butter
• softened
• 2 tbsp milk
• 3-4 drops peppermint flavour oil
• 2 tbsp dark chocolate chips

Directions

• Line a 24x35cm/9½x14in Swiss roll tin with greaseproof paper and preheat the oven to 180C/350F/Gas 4.
• Melt the chocolate in a heat-proof bowl set over a pan of simmering water.
• Whisk the egg yolks with the sugar in a bowl. Add the cocoa powder
• stir to combine until the mixture has thickened
• is pale and increased in volume.
• Whisk the egg whites in a separate bowl until stiff.
• Pour the melted chocolate into the egg yolk and sugar mixture. Stir until the chocolate is fully incorporated.
• Gently fold in the egg whites.
• Pour the mixture into the prepared tin. Tilt the tin so that the mixture spreads into the corners.
• Bake for 18-20 minutes
• or until firm and springy to touch.
• Once cooked
• turn the roulade out onto a piece of greaseproof paper dusted with caster sugar.
• Gently remove the lining paper and cover with a damp tea towel. Leave to cool completely.
• For the filling
• gradually add the icing sugar to the softened butter. Beat until all the icing sugar is incorporated. Add the edible peppermint oil to the milk
• and then stir into the buttercream.
• Spread the filling onto the cooled roulade
• leaving a 1.5cm/¾in gap at each edge. Sprinkle over the chocolate chips.
• Using the greaseproof paper to help you
• roll up the roulade from one of the short ends. Don’t worry if it cracks a little. Transfer onto a serving plate.