Bibim guksu, a cold dish made with very thin wheat flour noodles called somyeon with added flavorings, is one of the most popular traditional noodle dishes in Korean cuisine. It is also called guksu bibim or goldong myeon, all of which literally mean "stirred noodles" or "mixed noodles".  The dish is especially popular during summer.
There are many kinds of cold noodle dishes in Korea, including one made with cold beef broth; however, spicy cold noodles have historically been appreciated by spice-loving people in Korea and recognized internationally. What makes this dish so distinct from other cold noodle dishes from different cultures is the strong spicy flavor produced from the combination of red pepper powder, gochujang, and minced garlic, along with a sweet-and-sour flavor created by vinegar and sugar. Most spicy cold noodles are prepared with a slight touch of sesame oil to enhance the richness of its flavor.
Typically the dish would be prepared by stir frying diced beef, julienned pickled cucumbers, and mushrooms in sesame oil, which is all mixed together with the cooked noodles, soy sauce, sesame oil, sesame seeds and sugar. Garnishes placed on top and around the spicy noodles include hard-boiled eggs, pickled mu, dried gim strips, sliced cucumbers, and sometimes sliced Korean pear or tomato.