This section is from the book "The American Woman's Cook Book", by Ruth Berolzheimer. Also available from Amazon: The Domestic Arts Edition of the American Woman's Cook Book.
Caper Sauce - Add 2 to 4 tablespoons chopped capers.
Celery Sauce - Add 1/2 cup chopped cooked celery.
Cheese Sauce - Add 2 to 4 ounces grated cheese. Set over hot water and stir until the cheese is blended with sauce. Season to taste with mustard and paprika.
Cream Sauce - Use cream instead of milk in white sauce.
Egg Sauce, No. 1 - Add 1 hard-cooked egg, chopped.
No. 2 - Beat an uncooked egg, dilute with 1 tablespoon of hot thin white sauce, then beat this into the remainder of a cup of sauce. If the egg white is beaten separately, the sauce will be foamy.
Lobster Sauce - Add 1/2 cup finely flaked cooked lobster.
Mock Hollandaise Sauce - Pour sauce over 2 slightly beaten egg yolks, 2 tablespoons each of butter and lemon juice, beat thoroughly and serve immediately.
Mushroom Sauce - Add 1/2 to 1/3 cup chopped or sliced cooked mushrooms to sauce.
Olive Sauce - Add 1/4 cup chopped ripe or stuffed olives.
Oyster Sauce - Heat 1 pint small oysters in their own liquor to boiling point. Remove from heat after they have cooked 1/2 minute and combine with sauce. Season to taste.
Parsley Sauce - Add 2 to 4 tablespoons chopped parsley.
Shrimp Sauce - Add 1/2 cup chopped cooked shrimp.
Soubise Sauce - Rub 4 boiled onions and 2 sprigs parsley through a coarse sieve. Combine with sauce.
Tomato Cream Sauce - Cook 1 cup fresh or canned tomatoes, 1 stalk celery, 1 slice onion, 1/2 teaspoon salt and a few grains cayenne together for 20 minutes. Rub through a sieve. Add gradually, stirring constantly, to white sauce.
Veloute Sauce - Use 1 cup well-seasoned white stock for milk in thin or medium white sauce.
Yellow Sauce - Add hot sauce to 1 or 2 slightly beaten egg yolks and beat thoroughly.