A rich and delicous holiday treat with a hint of rum and lots of chocolatey goodness.
Preheat the oven to 375F.
Grease, line and flour a 16 x 11 inch swiss roll tin.
Whisk together egg yolks and 2 Tablespoons of sugar.
Whisk the egg whites in a separate bowl with cream of tartar until they form soft peaks.
Add the remaining sugar and whisk until peaks are stiff and glossy.
Fold half the flour into the yolk mixture.
Add a quarter of the egg whites and fold in to lighten the mixture.
Fold in remaining flour, then the rest of the egg whites.
Spread the mix in the cake tin.
Bake for 15 minutes.
Turn on to parchment paper sprinkled with granulated sugar.
Roll up and leave to cool.
In a heavy saucepan bring cream to boil.
Put chopped chocolate in two separate bowls and divide the cream over white and semi sweet chocolate.
Stir until chocolate has melted in each bowl, then beat one at a time until both mixtures are fluffy and thickened.
Mix a third of the semi sweet chocolate mixture with the rum or Cognac.
Unroll the cake and spread the white chocolate mixture first.
Re roll the mixture.
Spread the chocolate cream over the cake.
Mark with a form, and add your decorations and dust with extra cocoa.