A consommé is made by adding a mixture of ground meats or mousselin with Mirepoix, tomatoes, and egg whites into either bouillon or stock. This is then slowly brought to a simmer, and carefully kept there until the desired product is reached. The act of simmering brings impurities to the surface of the liquid, which are further drawn out due to the presence of acid from the tomatoes. Eventually, all the solids will form a 'raft' at the surface of the liquid, which is held together by the egg protein. The resulting concoction is then a clear liquid that has either a rich amber colour (for beef or veal consommé) or a very pale yellow colour (for poultry consommé). It is then carefully drawn from the pot and passed again through a filter to ensure its purity, and then is put through the lengthy process of skimming all visible fats from its surface. When meat is being prepared for consommé, as much fat as possible should be trimmed. Cartilage and tendons should be included because these contain gelatin, which enhances the flavor of the soup. If beef or veal is used, shin meat is ideal because it is very low in fat, very high in gristle, and undesirable for most other purposes. The meat is best if it is ground very fine into mousselin.
Consommés are usually served piping hot because they tend to cool down more quickly than other soups and form a gel when they do. They are most often served with garnishes which vary in complexity from a simple splash of sherry or egg yolk, to cut vegetables, to shaped savory custards called 'royales'. Consommés are ideal for whetting the appetite of the diner, especially in the traditional seven-course meal format, as they are very rich and tasty in flavour, but are neither filling nor heavy-feeling after consumption.
Consommés tend to be both expensive and difficult to make. A large amount of meat can yield a small amount of consommé. In some recipes, as much as a pound of meat can go into a single 8oz serving. The difficulty stems from the relatively complex clarification process involved in making it, which can often fail the impatient, careless, or inattentive cook.
Despite, or perhaps because of, these limitations, consommé has maintained its place as one of the most highly regarded and appreciated soups in the world.
Double consommé is a consommé which has been made to double strength. There is considerable disagreement among chefs as to how it is made. While some say that it is made by using twice the normal quantity of meat, there are others that say it is made to normal strength and then reduced (cooked down) by half, and others that say it's a consommé made from a stock or broth that used consommé as its liquid component. It is often used in other cold-cuisine items, especially those which use aspic, or natural gelatin.
Another variation that is often seen is cold jellied consommé, which, as the name implies, is served cold, and has more gelatin in it.
Clarified broths called consommés have been in use since the Middle Ages, taking many forms from simple soups, to displays of excess made from the meat of a wide variety of less-common animals.
A special type of consommé that was boiled solely with tendons and cartilage without the addition of salt was sweetened, flavoured with fruits and served as dessert. These sweetened consommé creations are essentially the forerunners of present-day gelatin desserts.