Mince the cucumber, and cut the hard-boiled egg in half. Combine the sauce ingredients.
Blanch the thinly-sliced beef in salted dashi stock. Allow to cool, then cut into bite-sized pieces.
Boil the cold noodles, then cool. Strain and mix in the sauce and the beef.
Transfer to a plate or bowl, top with the cucumber and egg, and it's complete!
If you want to prepare it more healthy, omit the sesame oil in the sauce, and increase with equal parts of water. One tablespoon of sesame oil is about 160 kcal.
Story Behind this Recipe
I learned this from a Korean friend. Apparently this level of spiciness is the norm in Korea.
This is pretty spicy, so if you want to tone it down a bit reduce the amount of gochujang and water. However since the spiciness and sweetness of gochujang varies by maker, please adjust accordingly. You can use the same sauce with bibimbap. I recommend using the leftover soup stock you boiled the beef in for a wakame soup (Recipe ID: 261566).