Remove it from the oven and don't panic as it sinks down, because this is quite normal. It's important not to overcook it, otherwise it will be difficult to roll. It will look very puffy, but a little finger gently pressed into the centre should reveal that it is cooked. 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. 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. Then, using a spanking clean bowl and carefully washed and dried beaters, whisk the egg whites to the soft-peak stage. 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. 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. 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. 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. 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. Next beat the 2 egg yolks, first on their own and then into the warm chocolate mixture. Then remove the pan from the heat and wait for the chocolate to melt before beating it with a wooden spoon until smooth. Now place the basin over a saucepan of barely simmering water, making quite sure the basin isn't actually touching the water. To do this, break the pieces of chocolate into a basin and add 3½ fl oz (100mls) warm water. You can make the chocolate filling well ahead of time.