The signature dish of Chiang Mai in northern Thailand, khao soi is a unique curried noodle dish with a rich, multi-cultural history. While there are numerous variations, the basic dish consists of egg noodles and meat in a coconut milk and curry broth, topped with fried noodles. Each diner adjusts the flavor of the dish to his or her taste with a variety of condiments served on the side. Restaurant menus may identify it with a variety of other spellings such as kao soi.
While this dish is most commonly associated with northern Thailand, it is believed to have originated elsewhere. Its roots have been traced back to Muslim groups who followed the Mongols when they invaded China in the 13th century. They settled in scattered groups in China, primarily making their living as farmers. In the late 1800s, they migrated again due to political upheaval in China, moving through Burma and Laos before settling primarily in northern Thailand. As they intermarried with the local population, elements of their culture were integrated into society, and this tasty dish evolved as cultures melded together.
Translated into English, khao soi means cut rice or chopped rice. It is believed that the original dish was served with rice noodles. These noodles were traditionally made from ground rice and other ingredients mixed into dough. The dough was then rolled out in a thin sheet and cut into the noodles used in this dish.
Due to the halal eating requirements of Islam, khao soi was originally made without pork. Contemporary versions of the dish, however, include a choice of a variety of meats including pork, beef, and chicken. Meat in khao soi may be in the form of tender chunks in the broth or pieces of meat falling off the bone. Vegetarian options are also available, especially where the dish has been adapted outside of Thailand for local tastes.
The dish is accompanied by a variety of condiments such as dried curry paste or hot chili sauce, lime wedges, shallots, pickled cabbage, and others. Each diner adjusts the sweetness or sourness of the dish to his or her individual taste with the addition of condiments. To make mixing condiments into the dish easier, khao soi and other Thai dishes are often served in a large bowl that is less than half full.
Khao soi is traditionally eaten at mid-day and is rarely served in northern Thailand in the evening. Diners traditionally enjoy this dish with the aid of chopsticks and a spoon. As khao soi is served around the world, however, local eating habits may take precedence as to when it is served and eaten.