Chef Jeong-sun
Aehobak-guk (애호박국, Korean Zucchini Soup)
A clean summer soup of Korean zucchini and salted shrimp, built on quick anchovy-kelp broth and finished before the half-moons lose their shape on a weeknight table.
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Kongnamul-naengguk (Cold Soybean Sprout Soup)
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A cold Korean soup built from the water the soybean sprouts cooked in, chilled hard and seasoned lightly so the broth stays clean, nutty, and sharp enough for summer rice.
Soups & Stews
Korean
Weeknight
Quick Meal
Comfort Food
15 min
Active Time
10 min cook•2 hr 25 min total
Yield4 servings
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.
Naengguk, cold soup, is a practical Korean summer category rather than a court dish: homes made it from cucumber, seaweed, young radish kimchi brine, or soybean sprout broth when heat made heavy soups unwelcome. Kongnamul became a dependable everyday ingredient because soybeans sprout quickly, cheaply, and in every season, which is why kongnamul-guk and its chilled version are found more often on home tables than in formal records. The cold version keeps the same thrift as the hot soup but changes the seasoning, using vinegar and a harder chill to make the broth refreshing.
The technique, the tradition, and the story behind every dish.
Discover Culinary ExplorerIngredients
soybean sprouts (kongnamul)
Quantity
300g
rinsed and brown tails trimmed if desired
water
Quantity
6 cups
garlic
Quantity
2 cloves
lightly crushed
kosher salt
Quantity
1 teaspoon, plus 1/4 teaspoon more if needed
soup soy sauce (guk-ganjang)
Quantity
1 tablespoon
rice vinegar
Quantity
2 tablespoons
sugar
Quantity
1 teaspoon
scallion
Quantity
1
thinly sliced
green chili or mild green pepper (optional)
Quantity
1
thinly sliced
toasted sesame seeds
Quantity
1/2 teaspoon
chili threads (sil-gochu) (optional)
Quantity
small pinch
ice cubes (optional)
Quantity
4 to 6
| Ingredient | Quantity |
|---|---|
| soybean sprouts (kongnamul)rinsed and brown tails trimmed if desired | 300g |
| water | 6 cups |
| garliclightly crushed | 2 cloves |
| kosher salt | 1 teaspoon, plus 1/4 teaspoon more if needed |
| soup soy sauce (guk-ganjang) | 1 tablespoon |
| rice vinegar | 2 tablespoons |
| sugar | 1 teaspoon |
| scallionthinly sliced | 1 |
| green chili or mild green pepper (optional)thinly sliced | 1 |
| toasted sesame seeds | 1/2 teaspoon |
| chili threads (sil-gochu) (optional) | small pinch |
| ice cubes (optional) | 4 to 6 |
Equipment Needed
- •Medium pot with a tight-fitting lid
- •Fine strainer
- •Heatproof bowl or pitcher
- •Metal serving bowls, chilled if possible
Instructions
- 1
Clean the sprouts
Rinse the soybean sprouts in two changes of cold water, lifting them out so grit stays behind. Trim only the brown tails if they bother you. Do not remove every root for a weeknight soup; the sprouts should still look like themselves.
- 2
Boil covered
Put the sprouts, water, crushed garlic, and 1 teaspoon salt in a medium pot. Cover with a tight lid and bring to a boil over medium-high heat. Once it boils, cook 6 minutes without lifting the lid. Pick one method and stay with it: lid on the whole time, or lid off the whole time. Halfway is where the harsh beany smell comes from.
The water will look too plain now. Trust it. The soybean heads give the broth its nutty body while it cools. - 3
Separate and cool
Turn off the heat. Lift the sprouts into a bowl with tongs, then strain the cooking broth into a clean heatproof bowl or pitcher. Discard the garlic. Let both sprouts and broth cool 15 minutes at room temperature, then refrigerate until very cold, at least 2 hours.
- 4
Season cold
When the broth is cold, stir in the soup soy sauce, rice vinegar, and sugar. Taste it now. It should be clean, lightly salty, and a little sharper than you expect, because the sprouts and ice will soften it. Add the extra 1/4 teaspoon salt only if the broth tastes flat.
- 5
Assemble the soup
Divide the chilled sprouts among four bowls and pour the seasoned cold broth over them. Add scallion, green chili if using, sesame seeds, and a few chili threads. Add ice only at the table, just before eating, so the broth stays bright instead of watery.
Chef Tips
- •Buy soybean sprouts with yellow heads, pale firm stems, and no sour smell. If the heads are dark or the stems feel slick, cook something else. My teacher would have sent them back without a word.
- •Do not season the broth hot. Vinegar tastes different when chilled, and cold food needs salt judged cold. This is why the recipe waits.
- •Soup soy sauce gives savor without darkening the broth too much. If you only have regular soy sauce, use 2 teaspoons instead of 1 tablespoon and make up the salt carefully.
Advance Preparation
- •Boil the sprouts and chill the broth up to 24 hours ahead. Keep the sprouts and broth separate until serving so the sprouts stay crisp.
- •Once seasoned, the soup is best eaten the same day. The vinegar keeps its edge, but the sprouts soften after a night.
Frequently Asked Questions
Nutrition Information
1 serving (about 430g)
Calories
125 calories
Total Fat
5 g
Saturated Fat
1 g
Trans Fat
0 g
Unsaturated Fat
4 g
Cholesterol
0 mg
Sodium
950 mg
Total Carbohydrates
10 g
Dietary Fiber
1 g
Sugars
1 g
Protein
11 g
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