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What is Japanese Clear Soup?
Alongside miso soup, Osumashi (おすまし) is another classic Japanese soup (osuimono). Also called sumashi-jiru (すまし汁), this Japanese clear soup is made with dashi and lightly seasoned with salt and soy sauce.
With just a few ingredients, good-quality dashi is key to this soup’s delicate, savory flavor. Seasonal ingredients add color and texture, while light-colored soy sauce keeps the broth light in color.
It’s often served on special occasions, including Japanese New Year, Hinamatsuri (Girls’ Day), and seasonal celebrations.
My Recipe Story
What I love about osumashi is how a few simple ingredients let the flavor of good dashi shine through. For this version, I use kamaboko, shiitake mushrooms, mitsuba, and flower-shaped fu, but you can change the ingredients with the seasons. I like serving it with takikomi gohan and a few vegetable side dishes for a simple Japanese meal.
If you enjoy Japanese soups, try Homemade Miso Soup, Japanese Egg Drop Soup, Kabocha Miso Soup next!
Key Ingredients for Osumashi
- Dashi – Japanese soup stock made with kombu and katsuobushi forms the flavorful foundation of this soup. I recommend homemade dashi or a Dashi Packet. For a vegan version, use Vegan Dashi and omit the kamaboko.
- Light-colored soy sauce (usukuchi shoyu) – Adds savory flavor while keeping the broth light in color. Despite its name, it’s saltier than regular soy sauce. Look for it on Amazon or at Japanese or Asian grocery stores.
- Salt – Enhances the dashi’s flavor without darkening the broth.
- Kamaboko (fish cake) – Adds a savory flavor, springy texture, and a touch of color. Omit it for a vegan or vegetarian soup.
- Fu (wheat gluten) – These light, dried pieces soak up the flavorful broth. I use flower-shaped fu for a decorative touch. Soak in water until soft, then gently squeeze before using. Omit for a gluten-free version.
- Mitsuba (Japanese parsley) – Adds a fresh, distinctive aroma and a splash of green. Add just before serving to preserve its delicate fragrance.
How to Make Osumashi
- Make the dashi. Prepare Awase Dashi with kombu and katsuobushi, then strain.
- Prepare the ingredients. Soak the fu until soft and gently squeeze out the water. Slice the shiitake mushrooms and kamaboko, and tie the mitsuba stems into knots.
- Season the broth. Add salt and light-colored soy sauce to the dashi.
- Warm and serve. Add the mushrooms and kamaboko to the broth and heat through. Place the fu and mitsuba in individual bowls, then ladle the hot soup over them.
Nami’s Recipe Tips
- Start with good-quality dashi. Dashi is the foundation of this delicate soup, so take the time to make it from scratch. For a shortcut, I recommend a dashi packet rather than dashi powder.
- Use light-colored soy sauce. It keeps the broth’s color light. Despite its name, it contains slightly more salt than regular soy sauce.
- Choose seasonal ingredients. Try nanohana (rape flower), snow peas, or bamboo shoots in spring; myoga ginger, corn, or okra in summer; mushrooms, turnips, or chrysanthemum greens in fall; and nagaimo/yamaimo, lotus root, or komatsuna in winter.
- Cook additional vegetables separately as needed. The ingredients in this recipe don’t need pre-cooking. However, cook dense root vegetables and greens that may release color, such as spinach, separately before adding them to the broth. This helps keep the soup clear. Add them at the end and heat through before serving.
Make Ahead Tips
Prepare the dashi a day ahead and refrigerate it separately from the soup ingredients. For the freshest aroma and best texture, add the mitsuba and softened fu just before serving.
Storage and Reheating Tips
To store: Refrigerate leftover soup in an airtight container for up to 2–3 days. Store the mitsuba and fu separately, if possible.
To reheat: Gently warm the soup in a saucepan over medium-low heat until hot. Avoid a rolling boil to preserve the delicate broth. Add the mitsuba and softened fu to the serving bowls, then ladle the hot soup over them.
What to Serve with Japanese Clear Soup
This simple yet elegant soup fits beautifully into an ichiju sansai (one soup three dishes) meal. Serve it with these dishes:
- Takikomi Gohan (Japanese Mixed Rice) – Seasoned rice with vegetables makes a satisfying pairing for the delicate broth.
- Miso Cod – The soup offers a light, refreshing contrast to the rich, buttery fish.
- Napa Cabbage Pickles – These crisp, lightly salted pickles add a refreshing bite between dishes.
- Kinpira Gobo – Burdock root and carrots bring earthy flavor, sweet-savory seasoning, and a pleasant crunch to the meal.
FAQ
Can I use regular soy sauce instead of light-colored soy sauce?
Yes, although the broth will be darker and have a slightly different flavor. Start with a little less and adjust to taste.
Can I make this soup vegan?
Yes! Use kombu dashi or vegan dashi and omit the kamaboko fish cake. You can add tofu or extra mushrooms instead.
I’d love to hear how yours turned out! 💛 Please leave a star rating and comment below to share your experience. Your feedback not only supports Just One Cookbook but also helps other home cooks discover recipes they can trust.
Japanese Clear Soup (Osumashi)
Ingredients
For the Broth
- 3⅓ cups dashi (Japanese soup stock) (I used Awase Dashi (recipe follows) using kombu and katsuobushi; for vegan/vegetarian, make Vegan Dashi)
- 2 tsp usukuchi (light-colored) soy sauce (use gluten-free soy sauce for GF)
- ½ tsp Diamond Crystal kosher salt (use half the amount or the same weight for table salt)
For the Soup Ingredients
- 8 slices kamaboko (fish cake) (skip for vegan/vegetarian)
- 8 pieces fu (wheat gluten) (skip for gluten-free)
- 2 shiitake mushrooms
- 4 sprigs mitsuba (Japanese parsley)
For the Awase Dashi
- 4 cups water
- 1 piece kombu (dried kelp) (10 g; 4 x 4 inches, 10 x 10 cm per piece)
- 1 cup katsuobushi (dried bonito flakes) (packed)
Instructions
Before You Start…
- Gather all the ingredients. Please note that this recipe requires a minimum steeping time of at least 30 minutes for the dashi stock.
- Sometimes, life happens and you just don‘t have 30 minutes to make dashi from scratch. On those occasions, you can use a Dashi Packet or Dashi Powder.
To Make the Awase Dashi
- Gather all the ingredients. Most Japanese recipes would say to gently clean the kombu with a damp cloth. However, these days, kombu is quite clean, so just make sure it doesn't have any mold spots and it‘s ready to use. Do not wash or wipe off the white powdery substance, as it has lots of umami. Put the water and kombu in a large bottle or measuring cup and let it steep on the counter for at least 30 minutes (or ideally, 2–3 hours in the summertime and 4–5 hours in the wintertime). You can also cold brew the kombu dashi overnight in the refrigerator.
- Add 1 piece kombu (dried kelp) and 4 cups water to a medium saucepan. If you have cold brew Kombu Dashi (previous step), add the Kombu Dashi and hydrated kombu to the pot.
- Turn on the heat to medium low and slowly bring it to almost boiling, about 10 minutes. Just before the dashi starts boiling gently, remove the kombu from the pot (discard or repurpose it in other recipes—suggestions follow). If you leave the kombu in the pot, the dashi will become slimy and bitter.
- Add 1 cup katsuobushi (dried bonito flakes) and bring it back to a boil again. Once the dashi is boiling, reduce the heat, simmer for just 30 seconds, and turn off the heat.
- Let the katsuobushi sink to the bottom, for about 10 minutes. Meanwhile, you can prepare the soup ingredients.
- Strain the dashi through a fine-mesh sieve over a bowl or measuring cup. The Awase Dashi is ready to use.
- Reserve the spent kombu and katsuobushi in an airtight container and store it in the refrigerator for a week or in the freezer for up to a month. See the instructions below for how to repurpose them.
To Prepare the Ingredients
- Tips: The ingredients I use here do not require pre-cooking. If you want to add different ingredients to Osumashi, be sure to first cook separately any ingredients that require cooking, then add them to the soup later. These include dense root vegetables or leafy greens that may release color, such as spinach. Once all the ingredients are cooked, simply add them to the clear soup to warm up.
- Soak 8 pieces fu (wheat gluten) in water for 10 minutes. Once soft, gently squeeze out the water.
- Discard the stems of 2 shiitake mushrooms and thinly slice them about ¼ inch (6 mm) thick.
- Make a knot in each of the stems of 4 sprigs mitsuba (Japanese parsley). Detach the wooden board of the kamaboko by sliding the knife under the fish cake. Then, thinly cut 8 slices kamaboko (fish cake) about ⅛ inch (3 mm) thick.
To Make the Soup
- Divide and add the rehydrated wheat gluten and mitsuba to the individual bowls.
- Next, make the clear soup broth. Add 3⅓ cups dashi (Japanese soup stock) back to the pot and season with 2 tsp usukuchi (light-colored) soy sauce and ½ tsp Diamond Crystal kosher salt (use half the amount or the same weight for table salt).
- Add the kamaboko fish cake slices and shiitake mushrooms to the pot and heat until warm. Serve the soup in the individual bowls.
- Enjoy!
To Store
- Let your soup cool to room temperature and then refrigerate for up to 2–3 days. It‘s best to add the mitsuba and wheat gluten just before serving.
What To Do with the Spent Katsuobushi and Kombu?
- With the spent kombu, you can make Simmered Kombu (Kombu Tsukudani).
- You can also repurpose the spent kombu and katsuobushi to make Homemade Furikake (Rice Seasoning).
Nutrition
The nutrition facts shown are generated by an online calculator and are estimates only. Please consult a professional nutritionist for specific dietary needs.
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