Mix mascarpone, sugar, and vanilla sugar until creamy. Cover and refrigerate for 15 minutes.
If using fresh cherries, wash and pit them. If using canned cherries, drain well and discard the juice.
Arrange amarettini biscuits in a bowl to cover the bottom completely. Drizzle with amaretto (or fruit juice for children). Choose the alcohol based on your fruit — amaretto pairs well with cherries for a subtle marzipan flavor.
Layer the cherries on top of the biscuits. Spread the chilled mascarpone cream over the cherries.
Garnish with chocolate flakes or cocoa powder, keeping the garnish moderate in sweetness.