Korean cold buckwheat noodles served in chilled broth are known as naengmyeon.
Naengmyeon consists of long, thin noodles made from buckwheat and other starches, including potato, sweet potato, arrowroot, or kudzu. The broth-based version is called mul-naengmyeon: it is served cold with a tangy broth, often alongside cucumber, Korean pear, pickled radish, boiled egg, and slices of beef. Vinegar and mustard are commonly added at the table.
The dish originated in northern Korea and has long been associated with Pyongyang and Hamhung. A 19th-century text, Dongguksesigi, records naengmyeon as a dish of the Joseon period. It spread widely across both North and South Korea after the Korean War.
A common mix-up is bibim-naengmyeon, which uses the same broad noodle tradition but is tossed with a spicy red dressing, usually based on gochujang, rather than served as a noodle soup. Thus, “naengmyeon” is the umbrella name, while the chilled-broth style is more specifically mul-naengmyeon.