chocolate chestnut rouladerating:
50g cocoa powder, sfited
6 large eggs, separated
150g golden caster sugar
½ teaspoon vanilla extract
icing sugar, for dusting
75g vacuum-packed cooked chestnuts
1 x 250g tin creme de marrons de l'Ardeche (sweetened chestnut purée), chilled
25ml Cognac (or cooking brandy will do)
50g mascarpone, chilled
25g icing sugar
200ml double cream, chilled
pre-heat the oven to gas mark 5, 350°F, 180°C.
you will also need a shallow baking tin, 9 x 13 in (23 x 45 cm) and ½ inch (1 cm) deep, lightly oiled, and lined with baking parchment - to stand 1 inch (2.5 cm) proud of the tin - plus an extra sheet of baking parchment for turning out the roulade.
first of all, in a large mixing bowl, and using an electric hand whisk, beat the egg yolks with the sugar and the vanilla extract on a high speed until the mixture has doubled in volume and is pale in colour - this will take about 10 minutes.
next, in a clean, grease-free bowl, whisk the egg whites until they form soft peaks. Then, using a large metal spoon, fold one third of the egg whites into the egg mixture and then fold in the rest and finally the cocoa powder. Pour the mixture into the prepared tin and bake for 20 minutes. Then leave the roulade to cool in the tin.
when the roulade is cold, turn it out on to a sheet of baking parchment (slightly larger than the roulade), which has been dusted with icing sugar.
for the filling, in a bowl, mix together the chestnut purée, Cognac (or cooking brandy), mascarpone and 1 oz (25 g) of icing sugar. In a separate bowl, whip the cream until it forms soft peaks, then roughly chop the cooked chestnuts.
peel away the lining paper and spread the chestnut mixture over the chocolate roulade, leaving a 1 inch (2.5 cm) gap all round.
sprinkle over the chopped chestnuts and spread the whipped cream over that. Holding the paper, roll the roulade widthways. Serve, generously dusted with icing sugar.