Claire's Christmas Chocolate Roulade

1. Preheat oven to 180oC. Line a 33x23cm Swiss roll tin with non-stick parchment. Melt the 175g plain chocolate in a bowl set over a pan of hot water or in the microwave on high for about 2 1/2 mins.

2. Put the yolks and sugar in a bowl over a pan of simmering water and whisk with an electric whisk until the mixture leaves a trail when blades are lifted (about 5mins). Whisk in the melted chocolate.

3. In a large bowl, whisk the egg whites into stiff peaks. Whisk a large spoonful into the chocolate mixture, and then fold in the rest.

4. Pour the mixture into the tin and shake gently to spread the mixture into the corners. Bake for 20mins until firm. Remove from the oven. Leave to cool for a few minutes. Place a clean damp tea towel over the cake with a board on top. Invert, remove the tin and peel away the baking parchment. Roll up the cake with the damp tea towel to keep the sponge moist. Leave to stand for about 5mins.

5. Meanwhile make the filling. Put the white chocolate in a heatproof bowl set over a pan of hot water. Heat gently, stirring occasionally, until the chocolate has melted. Leave to cool a little. Quickly fold into the whipped cream, taking care the chocolate doesn't split but sets to form a mousse. Whip the cream until it just holds its shape, then stir in the liqueur. Put a large sheet of greaseproof paper on the work surface, turn out the roulade, and peel off the backing paper. Spread with mousse evenly over and sprinkle with raspberries. With a short side towards you, mark an indent across the top 2.5cm in, then lift the paper and use to roll the roulade.

6. Coat with ganache - to make: boil whipping cream and then mix in the broken dark chocolate. Leave to cool until set.

7. Dust with icing sugar, decorate with chocolate leaves until it just holds its shape.

8. Serve with chocolate sauce and chantilly cream.