Combine the raspberries with the sugar in a bowl and set aside for a couple of hours, then drain off and discard any liquid.
Mix the brandy and other liqueur, set aside 2 tablespoons of this mixture and sprinkle the remainder over the raspberries.
Line a bowl of about 1.5 litre capacity with cling film. Cut the cake into long thin triangles and use to line the bowl, overlapping neatly and leaving no holes. Sprinkle generously with some of the reserved alcohol mixture.
Whisk the cream until it holds its shape. Stir in the ricotta, then gently fold in the raspberries and chocolate.
Fill the sponge-lined bowl with the raspberry cream mixture.
Once the bowl is filled, cover with more pieces cake, and sprinkle over the last of the alcohol.
Cover with cling film and chill in the fridge for at least 12 hours.
Just before serving, take the zucotto out of the fridge, unmould and peel off the cling film.
Cut into wedges. Dust with icing sugar and extra raspberries and serve.