Miso soup is a Japanese soup made by stirring miso paste into dashi, a light savory broth, then adding ingredients such as tofu and wakame. It comes together quickly, and adding the miso off the heat keeps its delicate flavor fresh rather than boiling it away.
Ingredients
- 4 cups (960 ml) water
- 1 piece kombu, about 4 inches (10 cm) long
- 1 cup (about 4 g) dried bonito flakes (katsuobushi)
- 3 tablespoons dried wakame seaweed
- 7 ounces (200 g) soft or medium-firm tofu, cut into ½-inch cubes
- 3 tablespoons white or yellow miso paste, plus more to taste
- 2 scallions, thinly sliced
Instructions
- Soak the kombu. Put the water and kombu in a saucepan and leave them to soak for 20 to 30 minutes if time allows. This helps draw out the kombu’s savory flavor. If you are in a hurry, you can start heating them right away.
- Make the dashi. Set the saucepan over medium heat. Remove the kombu just before the water reaches a simmer; do not boil it, as boiling can make the broth cloudy or bring out a slippery texture. Bring the water to a boil, turn off the heat, and add the bonito flakes. Let them steep for 5 minutes, then strain the broth through a fine-mesh sieve. Avoid pressing the flakes, which can make the dashi bitter. Discard the kombu and flakes.
- Prepare the wakame. While the broth is being made, cover the dried wakame with cold water in a small bowl. Soak for about 5 minutes, or according to the package directions, until it has expanded. Drain it and cut any large pieces into manageable lengths.
- Warm the soup ingredients. Return the strained dashi to the saucepan over low heat. Add the tofu and hydrated wakame, and warm gently for 2 to 3 minutes. The broth should be hot, but there is no need to boil it.
- Dissolve the miso. Turn off the heat. Put the miso in a small bowl, ladle in a little hot broth, and stir until smooth. Stir this mixture back into the saucepan. Alternatively, push the miso through a small strainer held over the pot, mixing it with the broth as it passes through. Taste and add more miso a teaspoon at a time if you want a stronger, saltier soup. Do not boil after adding the miso.
- Finish and serve. Stir in most of the sliced scallions, ladle the soup into bowls, and scatter the remaining scallions on top. Serve while hot.
Tips
- Choose miso to suit your taste. White miso (shiro) is usually mild and lightly sweet; yellow miso is more savory. Red miso tends to be stronger and saltier, so begin with less and adjust after tasting. Miso brands vary in saltiness.
- Keep miso out of a rolling boil. High heat can dull its aroma and flavor. Take the pan off the burner before stirring the paste in, and serve soon after.
- Use instant dashi if needed. For a faster version, dissolve instant dashi granules in 4 cups of water according to the package directions. Check whether they contain bonito, seafood, or other ingredients if you have dietary restrictions.
- Make it vegetarian or vegan. Skip the bonito flakes and use kombu dashi, or a vegetarian dashi product. Dashi made only from kombu has a gentler flavor; dried shiitake can be added for more depth.
Serving Suggestions
Serve miso soup as a small first course or alongside steamed rice, grilled fish, and simple vegetable dishes. It also pairs well with a Japanese-style breakfast of rice, eggs, or pickles. Since the broth is savory and can be salty, keep other dishes lightly seasoned and offer the soup in modest bowls. For a more filling meal, add extra tofu or vegetables and serve with rice.
Variations
The basic method works with many additions. Try thinly sliced mushrooms, such as shiitake or enoki, simmered in the dashi until tender; add them before the tofu. Thin slices of daikon, carrot, or potato also need time to soften, so simmer them in the broth before adding the miso. Spinach, napa cabbage, or sliced greens can be added near the end and cooked just until tender. Clams are another traditional option: simmer them in the dashi until they open, discard any that remain closed, then finish with miso. Avoid crowding the pot; a few additions let the broth remain clear and balanced.
Storage and Reheating
For the best flavor and texture, serve miso soup freshly made. If you expect leftovers, store the dashi, tofu, and vegetables separately from the miso when practical, then add miso after reheating. Refrigerate leftovers promptly in a covered container within 2 hours of cooking (within 1 hour if the room temperature is above 90°F/32°C), and use them within 3 days. Reheat gently on the stove until steaming hot, but do not boil; stir in fresh miso if the soup was stored without it. If already mixed, reheat only the portion you plan to eat. Freezing is possible for the broth, but tofu can turn spongy and wakame may soften, so freezing is not ideal for finished soup. Discard soup left at room temperature beyond the safe cooling window.
Frequently Asked Questions
Can I make miso soup without bonito flakes?
Yes. Make kombu dashi by soaking kombu in water, then heating it gently and removing it before the broth boils. For more savory depth, steep dried shiitake in the water and strain them out, or use a vegetarian dashi granule product.
Do I have to soak dried wakame first?
Usually, yes. A short soak rehydrates it and makes it easier to portion. Follow the package directions, since cut size and brands vary, and drain it before adding it to the soup. Dried wakame expands considerably, so measure it dry.
How much miso should I use?
Three tablespoons for 4 cups of broth makes a moderately seasoned soup, but the right amount depends on the miso and your preference. Start with that amount, taste, and add more gradually. Do not assume every brand has the same salt level.
Can I use firm tofu?
Yes. Soft or medium-firm tofu gives the soup a tender texture, while firm tofu holds its shape more readily. Cut it into small cubes and warm it gently so it does not break apart as you stir.
Why should miso soup not be boiled?
Boiling after the miso is added can weaken its aroma and make the soup taste less fresh. Heat the broth and additions first, switch off the heat, then dissolve and stir in the miso just before serving.
Is miso soup gluten-free?
It can be, but check the labels on the miso and dashi. Some miso is made with barley, which contains gluten, and prepared dashi products may include wheat or other additives. Choose products specifically labeled gluten-free if needed.