Chocolate Christmas log

Known in France as bouche de noel.  I am making one tonight to serve tomorrow when I have a group of friends coming for afternoon tea.

For the buttercream filling

100g /3.5 oz butter
150g/5oz icing sugar
55g/2oz cocoa powder
a splash of brandy or rum
Caster sugar for, dusting
cocoa powder, for sifting 
 

 Preheat the oven to 180C/350 Gas 4. Grease a 23 cm x 33 cm Swiss roll tin and line with baking parchment.

To make the sponge  

Sift the flour, cocoa and salt together and set aside. Sprinkle a large piece of greaseproof paper with caster sugar and set aside.
 Put the egg whites in a clean bowl and whisk until frothy. Add the cream of tartar and whisk until stiff. Gradually add the sugar until the mixture forms soft peaks.
Place the sugar in a bowl and the egg yolks and whisk until pale and thick. Add the almond essence. Using a large metal spoon, stir in the reserved flour and cocoa mixture. Finally, lightly fold in the egg whites until well blended - take care not to beat the air out of the mixture. Spoon the mixture into the Swiss roll tin and level the top. Bake for 15-20 minutes or until sponge-like to the touch. Turn the sponge onto the greaseproof paper dusted with caster sugar. Peel away the baking parchment and roll the sponge with the greaseproof paper inside. Leave to cool.Buttercream     Beat the butter in a mixing bowl until smooth and then gradually beat in the icing sugar and cocoa powder. Add the brandy and mix well.

 Once the sponge has cooled unroll it carefully and spread it with half the filling and roll it up again - without the greaseproof paper this time.  Spread the rest of the filling over the cake to cover it. Score it with a fork to resemble a log and dust with cocoa powder. Decorate with a sprig of holly.