Meringue is a mixture of egg whites and sugar that is beaten to a stiff foam. For a smooth texture the sugar must dissolve completely. To accomplish this, while beating the egg whites, add the sugar in small increments, a tablespoon at a time. There are two types of meringues, soft and hard. A soft meringue has less sugar than a hard meringue. Soft meringues are used as toppings for pies or baked Alaska. They are popped into the oven for browning. A hard-meringue mixture is generally spooned or piped with a pastry bag onto a parchment-lined baking sheet to form shells or small mounds. Meringues require long baking (one hour or more) at a low temperature (200° to 250°F) until they are firm and crisp. Allowing meringues to stand in the oven with the heat off for an additional hour or more ensures thorough drying. Hard meringue shells can be filled with fresh fruit or ice cream. Small round-shaped meringues, often containing bits of nuts, dried fruit or chocolate can be served as candies.