A Return to the Black Forest

You can make the chocolate filling well ahead of time.

To do this, break the pieces of chocolate into a basin and add 3½ fl oz (100mls) warm water. Now place the basin over a saucepan of barely simmering water, making quite sure the basin isn't actually touching the water. Then remove the pan from the heat and wait for the chocolate to melt before beating it with a wooden spoon until smooth.

Next beat the 2 egg yolks, first on their own and then into the warm chocolate mixture. As soon as the mixture has cooled, whisk the egg whites to the soft-peak stage then gently cut and fold them into the chocolate mixture. Cover the bowl with clingfilm and leave it in the fridge until you're ready to use it, but for a minimum of an hour. Drain the cherries in a sieve, discard the syrup, then place them in a shallow dish, spoon over the cherry brandy and leave aside till needed.

To make the base: first place the 6 egg yolks in a bowl and whisk them with an electric hand whisk until they begin to thicken. Then add the caster sugar and continue to whisk, but be careful not to overdo this, as it can eventually become too thick – stop when it falls off the whisk in ribbons. Now fold in the sifted cocoa powder. Then, using a spanking clean bowl and carefully washed and dried beaters, whisk the egg whites to the soft-peak stage. Then take 1 large spoonful, fold it into the chocolatey mixture to slacken it, and gently cut and fold in the rest of the egg whites.

Now pour the mixture into the prepared tin and bake the cake on the middle shelf of the oven for about 20 minutes or until it's springy in the centre. It will look very puffy, but a little finger gently pressed into the centre should reveal that it is cooked. It's important not to overcook it, otherwise it will be difficult to roll. Remove it from the oven and don't panic as it sinks down, because this is quite normal. Leave it until it's absolutely cold, then turn it out on a sheet of greaseproof paper, which has been lightly dusted with sieved cocoa powder. Then carefully peel away the silicone paper.

Drain the cherries again in a sieve placed over a bowl to catch the cherry brandy liqueur and sprinkle all but 1 tablespoon of the liqueur all over the base. Next remove the chocolate filling from the fridge and, using a small palette knife, spread it carefully and evenly all over the surface of the base. Next whip the double cream softly, and spread this all over the chocolate filling, leaving a good 1 inch (2.5 cm) border all round to allow for it spreading, then lightly press the cherries into the cream.

Rolling this cake up is going to be a lot easier than you think. All you do is take hold of one edge of the greaseproof paper beneath it, lift it and, as you lift, the cake will begin to come up. Just gently roll it over, pulling the paper away as it rolls. If the cake itself cracks as you roll it, this is not a problem – it's all going to get covered in chocolate anyway!

Now to make the chocolate curls for the topping – don't worry, it's much easier than it sounds – all you do is melt the chocolate as before, taking great care not to overheat it, then pour it on to an upturned plate 6 inches (15 cm) in diameter. Then place in the fridge for about 45 minutes until it's set. The chocolate should be firm when you touch it. If it's too soft it won't make nice curls.

To make the curls use a cheese slicer, or a very sharp knife will do if you hold the blade with both hands. Start at one end and just pull the slicer or knife along the surface of the chocolate towards you until curls form. As you make the curls, place them in a plastic container, as they're much easier to handle later on if they're well chilled. Put the container in the fridge. Now you can decorate the cake: spoon the cherry jam into a small saucepan, add the reserved tablespoon of liqueur from the cherries, warm it gently and then brush it all over the surface.  Place the chocolate curls all over that.  Finally, sift over a little cocoa powder to dust the surface lightly.