The ultimate frozen dessert for a dinner party. Semifreddo, meaning “half cold” in Italian, is known for its unique frozen texture, which falls somewhere between fluffy mousse and velvety ice cream. To achieve this, we wanted to whip as much air into the base as possible while still keeping the consistency rich and creamy. Since warmed eggs whip more easily than cold ones, we used a double-boiler method to gently heat the eggs. Whisking constantly helped cook the eggs without scrambling them. We found that store-bought jam was less likely to taste icy after being frozen in the semifreddo, unlike homemade jam. Swirling in the blueberry jam in stages kept the colorful layers distinct after slicing, and a splash of almond extract added notes reminiscent of amaretto, a traditional Italian liqueur often used to flavor semifreddo.