You can make this well in advance, it will keep for a week wrapped in double foil, or freeze it up to a month.
Ingredients
1 tsp butter
5 eggs, separated
140 g light muscovado sugar
100 g self-raising flour
25 g very good quality cocoa
caster sugar for dusting
285 double cream450 g fondant chocolate, such as Lindt Lindor
icing sugar
2 tbsp water
Method
Preheat the oven to 190° C Gas 5
1) lightly grease a 30x35 Swiss roll tin, then lined it with greaseproof paper
2) in a bowl whisk the egg yolks with 2 tbsp water and the muscovado sugar, until pale and thick, sift in the flour and cocoa, fold in gently with a large spoon
3) whisk the egg whites until they form peaks, then fold into the flour mixture, gently with a large spoon
4) pour the mixture in the tin, bake for 12 minutes, until the cake is firm to the touch
5) put a large piece of greaseproof paper on a work surface, and sprinkle with the caster sugar
6) turn the cake out onto the paper and peel of the lining paper, leave to cool
7) roll the cake, using the paper to help you, rolling the paper inside the cake
8) for the icing: bring the cream to the boil, remove from the heat, then break in 400g chocolate, stir until melted and smooth, leave to cool, chill for 1 hour 9) chop finely the rest of the chocolate, spoon a third of the icing in a bowl then mix with the chopped chocolate
9) carefully unroll the cake, then spread the filling over to within 2 cm of the edges, roll up the cake again using the paper to help you
10) cut a thick diagonal slice off one end of the cake, spread a little icing sugar over the cut side of the small piece, and fix to the side of the large roll to make a stump, spread the remaining icing over the cake,swirling it in an even layer with a palette knife, then dust with icing sugar.
