Line the bottom of a 2-litre glass bowl with the savoiardi biscuits, filling any gaps.
Drizzle 4 tablespoons of the amaretto liqueur over the biscuits. Add the cherry filling and set aside.
CUSTARD Use this recipe to make the custard and leave to cool
Put the amaretti biscuits in a clear food bag and roughly crush them with a rolling pin.
SPRINKLE Reserving a few of the crushed amaretti to decorate the top of the trifle, sprinkle the rest over the cherry filling. Drizzle the remaining 4 tablespoons of liqueur over.
Pour the warm custard over the top and leave to cool at room temperature.
Chill the trifle in the fridge overnight.
A few hours before serving, whip the cream to soft peaks and cover the top of the trifle. Sprinkle with the reserved crushed amaretti.