Korean Fermented Soybean Soup

Quick answer

Total time: 35 min
Level: Easy
Servings: 2 servings
Ingredients: 9

About this dish

Cheonggukjang-guk is a soup where cheonggukjang -- a short-fermented soybean paste with an assertive, pungent aroma that distinguishes it from the milder doenjang -- is dissolved into anchovy-kelp stock and simmered with zucchini, onion, and tofu.

The paste infuses the broth with a deep, earthy fermented quality that forms the core character of the soup. Zucchini and onion contribute natural sweetness that tempers the intensity of the fermented base, keeping the overall flavor approachable rather than overwhelming. Tofu is added partway through to absorb the broth without breaking apart, adding a soft textural contrast. Red chili flakes and sliced green onion go in at the end, lifting the finish with a gentle heat. Because cheonggukjang ferments faster and more aggressively than doenjang, its flavor is noticeably stronger -- starting with a smaller quantity and adjusting to taste is advised for first-time cooks.

Ingredients (2 servings)

Ingredient	Amount	Unit
fermented soybean paste (cheonggukjang)	180	g
firm tofu	150	g
zucchini	80	g
onion	70	g
green onion	30	g
minced garlic	1	tbsp
anchovy-kelp stock	700	ml
Korean chili flakes	1	tsp
soup soy sauce	1	tsp

Instructions

Read the steps as a cooking flow: prep, heat, seasoning, doneness control, and finish.

6 steps

1

Prep

Cut 80 g zucchini and 70 g onion into bite-size pieces, then slice 30 g green onion on the diagonal.

Cut 150 g firm tofu into 2 cm cubes and let excess moisture drain so it holds its shape later.
2

Control

Pour 700 ml anchovy-kelp stock into a pot and heat it over medium heat.

When small bubbles gather around the edge, the stock is hot enough to dissolve the paste without scorching it on the bottom.
3

Control

Add 180 g cheonggukjang a little at a time, pressing any lumps against the spoon until the broth looks evenly cloudy.

Lower to medium-low heat and simmer for 5 minutes so the fermented soybean flavor spreads through the stock.
4

Control

Add the onion, zucchini, and 1 tablespoon minced garlic, then simmer over medium heat for about 6 minutes.

Cook until the zucchini edges look slightly translucent and the onion softens, but avoid a hard boil that dulls the aroma.
5

Season

Add the tofu and warm it by spooning broth over the pieces instead of stirring hard, which can break them.

Add 1 teaspoon Korean chili flakes, then taste before adding soup soy sauce little by little because the paste may already be salty.
6

Finish

Add the green onion and simmer for 2 more minutes, then turn off the heat.

Cover the pot and let the soup rest for 3 minutes; when the sharp fermented aroma softens slightly, serve it hot.

Practical Cooking Checks

The cues that matter most while cooking.

Key technique: Cheonggukjang guk delivers the pungent, protein-rich depth of short-fermented soybeans and summer zucchini.
Finish cue: Cook until the zucchini edges look slightly translucent and the onion softens, but avoid a hard boil that dulls the aroma.