Mix water and alchermes in equal quantities.
Use 6 half sphere moulds (I used moulds of about 250 ml capacity).
With these amount of ingredients you’ll have delicious leftover.
Remove brown sides from the sponge cake and slice it, making 1 cm thick slices.
Line moulds with sponge cake slices pressing it down gently.
Spread with orange pastry cream semifreddo, filling half of the mould, then cover it with sponge cake slices and press gently.
Brush with alchermes and water mixture.
Spread with cocoa semifreddo and cover with sponge cake slices.
Wrap in cling film and put in the freezer for about 3 hours.
When completely set, remove from the freezer, turn out the dessert and brush the outer surface of the zuccotto with alchermes and water mixture.
You can serve it with a chocolate sauce, whipped cream or as it is.
If stored in the freezer for long time, remove it at least one hour in advance before serving, to allow it to defrost.