Kongnamul-naengguk (Cold Soybean Sprout Soup)

This dish lives or dies by one instruction: save the cooking water. People drain the soybean sprouts and then wonder why the soup tastes thin. The broth is not an afterthought here. It is the dish, pale and nutty from the sprouts, sharpened with vinegar only after it cools.

My mother made kongnamul-naengguk when the kitchen was too hot for another pot at dinner. She boiled the sprouts in the morning, cooled the broth in a metal bowl, and by evening there was soup cold enough to wake up plain rice. It belongs to the weeknight table, especially in summer, but don't treat it carelessly because it is quick. Soybean sprouts punish a loose hand: lift the lid halfway and the beany smell follows you around the room.

Boil them one way only: lid on from the start, or lid off the whole time. I give you the lid-on way because it keeps the broth clean and the sprouts crisp. Season after chilling, not before, because cold dulls salt and sharpens garlic differently. 손맛 is real; I measure it anyway, so the next bowl comes out the same.