Cookbook:Oyster sauce

Oyster sauce is a dark, savory condiment derived from oysters. Traditionally it is produced by reducing the liquid left over after boiling oysters, but many modern oyster sauces include some combination of sugar, salt, caramel color, oyster flavoring, and cornstarch. It is a staple in many cuisines, including Chinese, Thai, Vietnamese, and Malay.

Variations
Vegetarian substitutes for oyster sauce exist, and these use alternate ingredients such as mushrooms to produce the desired savory flavor profile.