Separate eggs. Beat the egg yolks with 60 g sugar until white-creamy. Sift flour on top and mix. Beat egg whites until stiff and fold in carefully. Spread the dough on a baking tray (32 x 39 cm) lined with baking paper. Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 8-10 minutes. Remove the sponge cake, turn out on a tea towel sprinkled with sugar and let it cool down for 30 minutes
Soak gelatine in cold water. Mix mascarpone with the chestnut cream for 2-3 minutes. Squeeze out the gelatine, melt in a pot at low heat, remove from the heat. Stir some chestnut cream into the gelatine. Stir the gelatine mixture into the remaining chestnut cream. Beat 150 g cream until stiff, fold in. Remove the baking paper from the sponge cake. Cut the sponge cake into 21 rectangles (approx. 5 x 10 cm), of which 1 rectangle may be cut into strips
Line a box mould (27 x 10 cm) with cling film. Line the mould with about 1/4 of the dough pieces. Pour approx. 1/3 of the cream on top and smooth it down. Pour 1/4 of the dough pieces on top, press down slightly. Repeat the process with the remaining pieces of dough and the rest of the cream, finishing with 1 layer of dough. At the end use narrow strips of dough if necessary. Cover with foil and chill for approx. 4 hours.
For the icing, chop the chocolate and put it in a bowl with butter. Bring 150 g of cream to the boil, remove the pot from the heat, allow to cool for 3-4 minutes. Pour cream over the chocolate mixture and stir occasionally with a wooden spoon until an even glaze is obtained
Take the mould out of the refrigerator, remove the upper foil. Turn the cake onto a cake rack, remove the remaining foil. Cover the cake with icing, drain and allow to set in a cool place. Caramelise 50 g sugar in a pan, remove from the heat. Turn the chestnuts one by one, place them on a greased aluminium foil and let them set. Arrange the cake on a plate, decorate with chestnuts
waiting time approx. 6 hours