Mul-naengmyeon (Cold Buckwheat Noodles in Broth)

Naengmyeon means "cold noodles," and mul-naengmyeon is the version served in broth (mul), as opposed to the spicy, dressed bibim-naengmyeon. The Encyclopedia of Korean Culture notes that naengmyeon is recorded in the mid-19th-century almanac Dongguk sesigi, in court banquet records (Jinchan uigwe) and in late-Joseon cookbooks such as Siui jeonseo and Buin pilji, so it was clearly established by the Joseon period. It developed in the north, where buckwheat grows well, using noodles of buckwheat flour with a little starch pressed through a noodle press.

Surprisingly to modern diners, it was a winter food. Dongguk sesigi lists naengmyeon among the seasonal dishes of winter and, the encyclopedia notes, judges the northwestern version the best. The encyclopedia's entry on Pyongyang naengmyeon paints the scene: noodles in ice-cold broth eaten on a heated ondol floor while temperatures outside fell to around −20 °C — fighting cold with cold. The broth was originally made with pheasant; beef and beef bones replaced it as pheasant became hard to find. See noodles in Korean history.

What makes the Pyongyang style, according to the encyclopedia, is the dongchimi: a mild, lightly salted radish water kimchi fermented in large jars buried in the ground, made with more radish than cabbage and little chili, whose ice-cold brine is mixed roughly half and half with skimmed beef broth. The broth is seasoned lightly, in keeping with the region's preference for food that is neither salty nor spicy.

After the Korean War, refugees from the north carried naengmyeon south, and it spread nationwide and became a year-round dish — today mostly a summer one. See making yuksu broth.

• Buckwheat: traditional noodles are made largely from buckwheat, a whole grain prized in the cold north; the share varies widely in commercial noodles.
• Lean protein: sliced beef shank and egg make the bowl fairly high in protein and low in fat, with zinc and vitamin B12 from the beef.
• Fermented brine: dongchimi adds a clean, lightly sour flavor; see fermented foods.

• Pyongyang naengmyeon (northern provinces): buckwheat-and-starch noodles in a mix of beef broth (formerly pheasant) and dongchimi, topped with sliced beef, kimchi, pear and boiled egg; mild and lightly seasoned. Vinegar, sugar and mustard are added at the table.
• Hamheung naengmyeon (northern provinces): chewy noodles of potato starch dressed with spicy raw-fish (hoe) and chili paste rather than served in broth — the origin of bibim-naengmyeon and hoe-naengmyeon.
• Jinju naengmyeon (Gyeongsang): pure buckwheat noodles in beef broth with boiled beef, egg-strip garnish and pear; the encyclopedia notes it uses no pork and was eaten more in winter than summer.
• Southern restaurant style: many restaurants serve chewier noodles with more starch and a sweeter, more vinegary broth than the classic northern style.