Biscuit tortoni

• 1 × 4 oz (113 g) packet macaroons
• 3 oz (75

Crush the macaroons to crumbs with a rolling pin. Sift the icing sugar on to a plate. Put the egg whites into a large mixing bowl and add the single cream, double cream and sherry. Whip the mixture until soft peaks form – takes about 5 minutes. Whisk in the icing sugar, then, using a metal spoon, fold in the crushed macaroons, reserving 2