Naengmyeon
Naengmyeon or raengmyŏn (랭면, in North Korea) is a noodle dish of northern Korean origin which consists of long and thin handmade noodles made from the flour and starch of various ingredients, including most commonly buckwheat (메밀, memil) but also potatoes, sweet potatoes, arrowroot starch (darker color and chewier than buckwheat noodles), and kudzu (칡, chik). Other varieties of naengmyeon are made from ingredients such as seaweed and green tea. In modern times, the mul naengmyeon (물 냉면) variant is commonly associated with and popularly consumed during the summer; however, it was historically a dish enjoyed during winter.
Source: Wikipedia
Recipes

Bibim-naengmyeon 비빔냉면 (Cold, spicy, chewy noodles) recipe by Maangchi
Today I’m going to show you how to make a spicy Korean icy cold noodle dish called bibim-naengmyeon. Unlike mul-naengmyeon (물냉면) it’s not very brothy, but it's still ice cold and made with a slightly sweet, vinegary, spicy sauce as well as some cucumber...