"Hot and sour soup" is a Chinese soup claimed variously by the regional cuisines of Beijing and Sichuan as a regional dish. The Chinese hot and sour soup is usually meat-based, and often contains ingredients such as day lily buds, wood ear fungus, bamboo shoots, and tofu, in a broth that is sometimes flavored with pork blood. It is typically made hot (spicy) by red peppers or white pepper, and sour by vinegar.
Samlor machu pkong or "Sour Shrimp Stew" is a Cambodian sour soup flavored with lemon, chilis, prawns and/or shrimp. One of the most popular sour soups in Cambodia, it is eaten most often on special occasions.
Samlar machu yuan or "Vietnam sour soup" is another common hot and sour soup of Cambodia originating among the Khmer Krom of the Mekong Delta region (hence, the name). It is made with fish, usually mudfish, walking catfish or tilapia, that has first been fried or broiled then added to the broth. Chicken may also be substituted. The ingredients which give the stew its characteristic flavor may vary depending on what is available locally to the cook. Possible ingredients include various combinations of pineapple, tomato, ngo gai, fried garlic, papaya, lotus root, Thai basil (Khmer: ជីក្រហម) and Thai chili.