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Cold soybean noodles, Kongguksu

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kid friendly
prep time: 
30 min
inactive time: 
240 min
cooking time: 
20 min
total time: 
290 min

Kongguksu is the perfect dish to help you cool off on a hot day. Traditionally eaten during the summer, this chilled soy milk noodle dish is hearty enough to eat year round. The homemade soymilk is the center of this soup.

Making soy milk is not as hard as you think. The soybeans are soaked, then cooked and pureed until smooth. The key to making soy milk for kongguksu is not to overcook the beans so that they retain their natural flavor. Add a dash of salt, perfectly cooked noodles and a fresh vegetable garnish to complete the soup. Kongguksu is great for vegans and vegetarians too.

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Main ingredients

10 ozKorean thin noodles 소면
11 ozSoybean 콩
5 cupsWater 물

For seasoning

1 tbsSalt 소금
1 tspSesame Seeds 깨

For garnish

½ Cucumber 오이
½ Tomato 토마토

Good to Know
How to Cook Noodles:
1. Put the noodles in boiling water.
(Make sure you have enough water in a pot. If you put too little, the noodles will become mushy and stuck together.)
2. When the water starts boiling up again, pour ½ cup of cold water.
3. Repeat when it starts boiling up again.
4. When the noodles are cooked, put them in COLD water immediately.
5. Wash them in cold water several times until no starch coming out.
6. Drain well.
Soaking Soybeans: If you don’t soak soybeans before boiling, your soybean broth may have a bad beany smell (콩비린내).
Seasoning: If you want to keep the soybean broth for later use, do not season when cooking. Adding salt will make the broth watery and sloppy.

More questions? Please leave your questions below in the comments section. We will do our best to answer as soon as we can.

Ingredient amounts in the recipe instructions are for the default serving size.
Click to enlarge photos.
Ingredient amounts in the recipe summary are for the default serving size.

1. Prepare soybeans

Wash 320grams of soybeans thoroughly (about 2-3 times). Soak them in water for 4 hours.

image: NKGSAA01.JPG

Wash & soak

  • 320g soybeans

2. Boil soybeans

Boil the soaked soybeans in boiling water on highheat for 5 minutes. (TiP: Don’t overcook or they may smell bad!)

image: NKGSAA02.JPG

Boil soybeans

  • High Heat image: highheat.png image: clock.png 5 min

3. Remove soybean skins

Rinse the cooked soybeans in cold water twice. Rub the cooked soybeans with your hands to remove the skins (some of them may have been removed already when washing). Add some water to let the skins float. Carefully pour the water out with the skins on top leaving the beans behind. Repeat this process until all the skins are removed.

image: NKGSAA03.JPG


  • cold water
  • 2 times

Remove skins

  • rub them with hands

Add water

  • let skins float
  • discard water and skins only


  • until all skins removed

4. Grind

Put the soybeans, 5 cups of water and 1 tablespoon of salt in a blender. (Or add salt when serving if you’re not using it right away.) Grind them until they get smooth and creamy like soybean milk. Keep it in the freezer while cooking noodles. (If you have enough time to make it icy cold before serving, refrigerate it.)

image: NKGSAA04.JPG


  • soybeans
  • 5 cups water
  • 1 tbs salt

Freeze (or refrigerate)

  • while cooking noodles

5. Prepare garnish

Wash & peel ½ cucumber. Don’t peel all the skin. Leave bits of skin randomly. Cut into 2” (or 5cm) long pieces and peel the flesh thinly while turning to create a thin sheet of cucumber flesh. Do not use the middle part (seeds). Julienne the cucumber flesh. If this method is too hard, just use the regular method of julienning cucumber. Then, wash and slice ½ tomato into wedges.

image: NKGSAA08.JPG


  • Wash & Peel
  • Cut into 2” (5cm) long
  • Peel thinly while turning
  • Discard Seeds
  • Julienne


  • Wash
  • Slice into wedges

6. Cook noodles

Boil 4 cups of water and 1 teaspoon of salt. Cook noodles in boiling water. When cooked, rinse in cold water 3-4 times and drain well.

image: NKGSAA06.JPG

Cook noodles

  • boiling water
  • add 1 tsp salt


  • 3-4 times
  • cold water


7. Serve

Place the cooked noodles in a bowl. Pour the chilled soybean broth over the noodles. Garnish with some cucumber and tomato and sprinkle some sesame seeds.(Add more salt if needed depending on your taste.) Enjoy!

image: NKGSAA07.JPG


  • in a bowl


  • chilled soybean broth


  • cucumber
  • tomato
  • sesame seeds

(Add more salt if needed)