Crumble the amaretti in a baking dish so that they cover the bottom by about 3 to 4 cm. Then drizzle them with eggnog. Add a layer of cream about 2-3 cm high, then the apple puree, another layer of cream about 2-3 cm high, and finally a layer of eggnog, so that the whipped cream is no longer visible through the liqueur.
To decorate the cake, sprinkle with amarettis.