Tom yum or tom yam (Lao: ຕົ້ມຍຳ [tôm.ɲám]; Thai: ต้มยำ, [tôm.jām] ( listen)) is a Lao and Thai, clear, spicy and sour soup.[1] Tom yum is widely served in neighbouring countries such as Cambodia, Brunei, Malaysia and Singapore, and has been popularised around the world.
Literally, the words "tom yum" are derived from two Tai words: "tom" and "yam". "Tom" refers to boiling process, while "yam" refers to a kind of Lao and Thai spicy and sour salad. Thus, "tom yum" is a Lao and Thai hot and sour soup. Indeed, tom yum is characterised by its distinct hot and sour flavours, with fragrant spices and herbs generously used in the broth. The basic broth is made of stock and fresh ingredients such as lemongrass, kaffir lime leaves, galangal, lime juice, fish sauce, and crushed chili peppers.