Add this to your dessert knowledge: Semifreddo means “half-cold” in Italian and refers to a chilled or half-frozen dessert containing whipped cream or meringue. This no-bake, partially frozen dessert borrows half of its texture from frozen mousse and the other half from gelato. Richly infused with finely-chopped basil and a puree of fresh strawberries, this is a simple and decadent make-ahead dinner party dessert.