1. A light dessert of stiffly beaten, sweetened egg white mounds that have been poached in milk. These puffs are then floated in a thin custard sauce. The dessert is also known as oeufs à la neige, "snow eggs. " 2. In France, île flottante ("floating island") is liqueur-sprinkled sponge cake spread with jam, sprinkled with nuts, topped with whipped cream and surrounded by a pool of custard.