Chocolate ice-cream sandwiches
Put the amaretti biscuits in a blender or food processor, and whiz until they form coarse crumbs.
Take one of the digestive biscuits and spread a 2.5cm/1in layer of ice cream on its non-chocolate side. Sandwich another biscuit on top, chocolate side uppermost. Squeeze the biscuits gently together and smooth the ice cream around the edges. Repeat with the remaining biscuits and ice cream.
Roll the edges of the biscuit sandwiches in the crushed amaretti biscuits to coat them, then place on a tray in the freezer. Freeze for at least 2 hours before serving.