To select and harmonize the materials for a mixed soup is one of the best evidences of culinary capacity; and the cook who can do this successfully, is qualified to prepare a soup of the most complex as well as one of the simplest character, without regard to its name or class.
These all belong to the white soup class, but they occupy so anomalous a position--an oyster soup being simply an oyster stew with additional liquid, and a thickening of flour--that they deserve special mention.
Rinse a quart of oysters in cold water, drain through a sieve. Put a piece of butter the size of an egg in a stew pan, and when melted add a pint of milk and let it come to a boil; add the oysters, and the moment the edges curl remove from the fire; season with salt and pepper. Serve with small crackers, or on thin slices of buttered toast.
Pour a pint of cold water over a quart of oysters, stir well and drain; put the liquor in a stew pan greased with butter; when it boils, skim, add the oysters, season to taste with butter, salt and pepper, and cook and serve as in No. 1.
In changing an oyster stew to a soup, the thickening and extra liquid should be added and cooked before the oysters are put into it.
These are French terms used to designate different kinds of soups; but they are applied so indiscriminately as to possess very little significance, even for culinary adepts; and the dividing line between a potage, a puree, a consomme, and an ordinary soup, is so imaginary as to be indistinct to plain every-day people. But as a foreign or grotesque name does not detract from the quality of a good thing, those who prefer to call a soup a potage, a puree or a consomme, can do so with impunity, and not legally infringe on the domain of any professional cook.
To scald stock or soup properly, it must be brought to the boiling point and thoroughly heated. Its liability to ferment and grow sour is only increased by merely re-warming it.
Vegetables when used merely to flavor soups should be simmered only long enough to extract their juices; and aromatic spices, orange and lemon juice, and other liquid flavorings whose subtle essences are driven off by heat, should be added barely a sufficient length of time before the soup is served, for them to blend and harmonize with the other materials--in fact it is usually better to put them in the tureen and pour the soup over them just before it goes to the table.