Nam pla, known in English as fish sauce and in Vietnamese as nuoc mam, is the primary seasoning in much of Southeast Asian cooking. Made by fermenting anchovies in brine, it has a pungent aroma and distinctive sea-saltiness. Viet Huong’s Three Crabs Brand is a high-quality variety and can be found in most Asian markets. Fish sauce is now available in most well-stocked major supermarkets and in all Asian markets. Soy sauce can be substituted in a pinch.