Line the box cake tin (11 cm x 25 cm; 1.25 litre capacity) with foil. Mix 4 tbsp. syrup and 4 tbsp. raspberry brandy. Soak 6 sponge fingers in it and lay out 3 pieces one after the other close to the edge of the box cake. Soak gelatine.
In the meantime, stir mascarpone, sour cream, sugar and 2-3 tbsp. syrup with the whisk of the hand mixer until smooth. Squeeze the gelatine, dissolve and mix with 3 tbsp. mascarpone mass. Then stir the rest of the mixture. Select the raspberries and fold in. Beat 150 g cream until stiff and fold in. Fill half of the raspberry mascarpone cream into the mould, smooth it down. Soak 6 biscuits and layer. Fill the rest of the mixture and 6 biscuits into the mould, smooth them down. Chill for about 3 hours. Turn out the cake onto a plate.
Beat 150 g cream until stiff and fold in. Fill half of the raspberry mascarpone cream into the mould, smooth it down. Soak 6 biscuits and layer. Fill the rest of the mixture and 6 biscuits into the mould, smooth them down. Chill for about 3 hours. Turn out the cake onto a plate. Whip 150 g cream until stiff, allow vanilla sugar to trickle in. Arrange the cream on the cake
waiting time approx. 3 hours