Khao Soi (or khao soy) is a type of curry popular in the North of Thailand, where many restaurants specializing in this dish can be found, especially in the ancient city of Chiang Mai, one of the most popular tourist destinations in the country. This coconut milk based soupy curry is usually made with chicken or beef and served over Chinese egg noodles garnished with crispy fried noodles, pickled mustard greens, shallots, lime, sweet soy sauce and spicy chili oil.