Korean Chilled Cucumber Soup
Quick answer
Oi-naengguk is a Korean chilled cucumber soup served in summer as a cold alternative to the hot soups (guk) that normally accompany Korean meals.
What makes this special
- Chilled cucumber slices float in a sharp vinegar broth to provide instant summer cooling.
- More vinegar means sharper coldness rivaling naengmyeon broth
- Floating ice cubes at serving completes the dish's core chill
Key ingredients
Core cooking flow
- 1 Rinse the cucumber, trim both ends, and slice it very thinly, about 2 mm thick.
- 2 Sprinkle the cucumber evenly with 1/4 teaspoon salt and let it stand for 5 minutes.
- 3 In a large bowl, first combine 700 ml water, 3 tablespoons vinegar, 1.5 tabl...
Oi-naengguk is a Korean chilled cucumber soup served in summer as a cold alternative to the hot soups (guk) that normally accompany Korean meals. When midsummer heat makes a steaming bowl of doenjang-guk unappealing, this icy broth takes its place at the table. Cucumber is sliced paper-thin and submerged in a broth of water seasoned with rice vinegar, soup soy sauce, salt, and sugar - a higher vinegar ratio intensifies the refreshing, palate-clearing sharpness. Ice cubes floated on top or at least thirty minutes of refrigeration are essential to achieve the chilling effect that defines the dish. Thinly sliced garlic infuses a mild pungency into the broth, and sesame seeds sprinkled on top add a nutty accent. Some versions include rehydrated dried seaweed, whose slippery texture contrasts with the cucumber's crisp snap. Alongside bibimbap or spicy banchan, oi-naengguk serves as a cooling counterbalance that tempers chili heat between bites.
Instructions
Read the steps as a cooking flow: prep, heat, seasoning, doneness control, and finish.
- 1Season
Rinse the cucumber, trim both ends, and slice it very thinly, about 2 mm thick.
Keep the slices even so the seasoning penetrates quickly and the texture stays crisp instead of chunky.
- 2Season
Sprinkle the cucumber evenly with 1/4 teaspoon salt and let it stand for 5 minutes.
When the slices bend slightly and release moisture, squeeze them firmly by hand so the broth will not taste diluted.
- 3Season
In a large bowl, first combine 700 ml water, 3 tablespoons vinegar, 1.5 tablespoons soup soy sauce, and 1 tablespoon sugar.
Stir until no sugar grains remain, since undissolved sugar makes the broth uneven.
- 4Season
Add 1/2 teaspoon minced garlic, then taste a spoonful of the broth.
If it feels flat rather than tangy and lightly savory, adjust with small pinches of salt so the vinegar is bright but not harsh.
- 5Season
Add the squeezed cucumber to the broth and loosen the slices with chopsticks so they are fully submerged.
Separate any clumps, because packed slices season unevenly and stay bland in the middle.
- 6Finish
Cover and refrigerate for at least 30 minutes so the cucumber absorbs the broth and the soup becomes thoroughly cold.
Just before serving, float 6 ice cubes on top and serve while the broth is icy.
After the steps
Pick a recipe that fits this dish.
Continue with shared ingredients, meal pairings, or a similar method.
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