Makguksu

Mak-guksu or buckwheat noodles is a Korean buckwheat noodle dish served in a chilled broth and sometimes with sugar, mustard, sesame oil or vinegar. It is a local specialty of the Gangwon province of South Korea, and its capital city, Chuncheon. Jaengban-guksu is a type of makguksu in which buckwheat noodles and various vegetables are mixed in a tray. Makguksu is closely related to naengmyeon, the archetypal Korean cold noodle dish. However, its differences lie in the high concentration of buckwheat flour in its noodles — the result of the grain being a staple crop in the Gangwon-do area, and the use of greater amounts of vegetables. The dish gets its name "rough noodles" because the buckwheat used is generally unhulled.

Source: Wikipedia