Tips: Oyster sauce is a richly flavored Chinese condiment made from oysters and brine. Vegetarian oyster sauces substitute mushrooms for the oysters. Both can be found in large supermarkets or at Asian specialty markets.
Shao Hsing (or Shaoxing) is a seasoned rice wine. It is available at most Asian specialty markets and in the Asian section of some larger supermarkets. If unavailable, dry sherry is the best substitute.
People with celiac disease or gluten-sensitivity should use soy sauces that are labeled "gluten-free," as soy sauce may contain wheat or other gluten-containing sweeteners and flavors.