Meringue

There are several types of meringue, which are foams that are usually made by whipping egg whites with sugar. In one particular type, known as French meringue, the foam is initially stabilized by the proteins in the egg whites and it is then baked until it is completely or partially dry. As it bakes, water evaporates and the sugar is concentrated in the walls of the foam, eventually forming a firm glass phase that makes the foam very stiff and stable. If all the water is not evaporated away, the outside of the meringue will still be stiff and crisp, but the inside will remain somewhat moist with an interesting soft and possibly slightly chewy mouthfeel.