Japanese miso soup is a savory broth made by dissolving fermented soybean paste into dashi, often with tofu, seaweed, and scallions. This approachable version uses instant dashi for a quick, deeply savory base, and adds the miso at the end so its aroma and flavor stay bright; ingredients and regional styles vary from home to home.
Ingredients
- 4 cups (950 ml) water
- 1 teaspoon (4 g) instant dashi granules, or the amount on the package for 4 cups (950 ml) water
- 3 tablespoons (about 54 g) white or yellow miso paste, plus more to taste
- 7 ounces (200 g) silken or soft tofu, cut into ½-inch (1.25 cm) cubes
- 1 tablespoon (about 2 g) dried wakame seaweed
- 2 scallions (about 20 g), thinly sliced
- 1 teaspoon (3 g) toasted sesame seeds, optional, for serving
Instructions
- Rehydrate the wakame. Put the dried wakame in a small bowl and cover it with cool water. Let it soak for 5 minutes, until the pieces have expanded and softened. Drain well and set aside. Wakame grows considerably as it absorbs water, so a tablespoon of dried seaweed is enough for this pot.
- Prepare the other ingredients. While the wakame soaks, cut the tofu into small, even cubes and slice the scallions thinly. Measure the water, dashi granules, and miso so they are ready to add. If the tofu is packed in water, drain it first; there is no need to press soft tofu.
- Make the dashi broth. Pour the water into a medium saucepan and stir in the dashi granules. Bring the broth to a gentle simmer over medium heat, stirring once or twice, for about 5–6 minutes. Follow the package’s directions if its recommended amount differs. Avoid a hard, rolling boil, which is unnecessary for dissolving instant dashi.
- Warm the seaweed and tofu. Add the drained wakame and tofu to the simmering broth. Lower the heat and cook gently for about 2 minutes, until everything is hot. Stir carefully so the tofu cubes keep their shape. The soup does not need to boil vigorously.
- Dissolve the miso separately. Turn the heat to low. Put the miso in a small bowl or ladle, add a few spoonfuls of hot broth, and stir until smooth. Pour this mixture back into the saucepan, stirring gently. Warm for another 1–2 minutes, but do not let the soup boil after adding the miso; a boil can dull its delicate aroma and make the broth taste harsher.
- Taste and serve. Taste a spoonful before adding any more seasoning, since dashi granules and miso vary in saltiness. If you want a stronger, saltier soup, dissolve in a little more miso using the same method. Ladle into bowls and top with scallions and sesame seeds, if using.
Tips
- Choose miso to suit the flavor you want. White miso, or shiro miso, is generally mild and a little sweet; yellow miso is more rounded and savory. Red miso is usually more assertive and salty, so start with less and adjust after tasting. Miso is not interchangeable spoon for spoon across every variety, and the best amount depends on the paste and your preference.
- Check the dashi label. Many instant dashi granules contain fish, commonly bonito, so they are not vegetarian. For a vegetarian soup, buy granules specifically labeled vegetarian or vegan, or use kombu dashi. Kombu is edible kelp; simmer a piece in the water according to the package’s directions, then remove it before adding the tofu. Kombu dashi tastes gentler and more sea-scented than bonito-based dashi.
- Use a ladle to avoid miso lumps. Miso paste can cling to itself if it is dropped straight into the pan. Whisking it with a little hot broth first makes it easy to blend evenly without vigorous stirring that could break the tofu. A small fine-mesh strainer can also be used to press the paste through into the pot.
- Keep the simmer gentle. Once the tofu is in the saucepan, use low heat and stir with care. Soft tofu can crumble if the soup is rapidly boiling or stirred forcefully. If you are making the soup ahead, store the broth and add delicate toppings close to serving for the best texture.
Serving Suggestions
Serve miso soup hot in small bowls as part of a Japanese-style meal. It pairs naturally with steamed rice, grilled fish, rice bowls, or a plate of vegetables. For a simple lunch, serve it alongside rice and a few small sides, such as cucumber salad or pickled vegetables. The soup is flavorful but light, so it works as a first course as well as a companion to a more substantial main dish.
Add the scallions just before serving so they stay fresh and aromatic. Sesame seeds are an optional garnish rather than a required ingredient; a small sprinkle gives a toasty note, but the soup is complete without them. If serving several people, taste the broth before ladling and keep extra dissolved miso nearby so guests can adjust their bowls without adding undissolved paste.
Variations
Make a vegetarian dashi version. Use vegetarian instant dashi or prepare kombu dashi instead of granules containing bonito. Dried shiitake can also add savory depth: soak a few dried mushrooms in water according to their package directions, strain the soaking liquid carefully, and use it as part of the broth. The result will have a deeper mushroom flavor and will differ from the cleaner taste of bonito dashi.
Change the vegetables. Thinly sliced daikon, carrot, or mushrooms can be simmered in the dashi until tender before you add the tofu and miso. Spinach or other tender greens need only a brief turn in the hot broth. Keep the total amount moderate so the vegetables do not overwhelm the soup or soak up too much broth. Different households and regions use different combinations, so treat these additions as flexible rather than a fixed formula.
Try different miso styles. Swap the white or yellow miso for red miso for a bolder, more deeply savory bowl, beginning with about 2 tablespoons (36 g) and adjusting to taste. A blend of two misos can balance sweetness and intensity. If you use a seasoned miso or salty dashi, add it gradually and taste before adding more; extra salt is rarely needed.
Use another topping. Cubes of cooked kabocha squash, a few sliced mushrooms, or thin strips of aburaage (fried tofu) can make the bowl more substantial. Aburaage is sold at many Japanese and Asian grocery stores; if you cannot find it, ordinary firm tofu can add body, though it will not have the same rich, fried flavor. Add ingredients that need cooking before the miso, and warm already-cooked toppings gently at the end.
Storage and Reheating
For food safety, refrigerate leftover soup within 2 hours of cooking, in a covered container. It keeps for 3–4 days in the refrigerator. The tofu may become a little firmer and the wakame softer as it sits, but the soup remains suitable to reheat if it has been chilled promptly. If the pot is still hot, divide it into shallow containers so it cools more quickly rather than leaving it on the counter to cool completely.
Reheat only the amount you plan to eat in a small saucepan over medium-low heat, stirring gently, until it is steaming hot throughout. For leftovers, USDA FSIS guidance is to reheat to 165°F (74°C); check with a food thermometer. Avoid a prolonged boil, especially if the soup already contains miso, as high heat can flatten its flavor and break up soft tofu. If you expect to freeze portions, the broth freezes better without tofu or wakame. Freeze promptly in a freezer-safe container, leaving room for expansion, for up to about 2 months for best quality. Thaw in the refrigerator, heat thoroughly, then add fresh tofu, seaweed, and dissolved miso.
Frequently Asked Questions
What is dashi, and can I make this soup without it?
Dashi is a Japanese soup stock that gives miso soup much of its savory foundation. It is often made with kombu, dried bonito flakes, or both, and instant granules are a convenient shortcut. You can use plain water if needed, but the soup will taste less complex. A vegetarian dashi product or kombu steeped according to its directions is a better substitute when you want depth without fish.
Can I use red miso instead of white miso?
Yes. Red miso works well, but it is often stronger and saltier than white miso. Begin with about 2 tablespoons (36 g), dissolve it in hot broth, and taste before adding more. The finished soup will have a deeper, more robust flavor. If you have more than one type of miso, blending them is another way to balance a mild and a bold paste.
Do I have to soak dried wakame first?
Soaking it separately for a few minutes makes it easy to judge the amount and remove excess soaking water before it goes into the pot. Some packages allow dried wakame to be added directly to hot broth, but it expands as it hydrates, so use a small quantity and follow the package directions. Do not substitute an equal volume of fresh seaweed for dried; their textures and amounts differ.
Why should I avoid boiling the soup after adding miso?
A brief boil is not needed to cook the paste, because miso is stirred into an already-hot broth. Keeping the soup below a boil helps preserve its fragrance and a cleaner, more balanced taste. Warm it gently after adding miso, and serve once it is hot. If the soup accidentally boils, it is still usable; the flavor may simply be less delicate.
Can I make miso soup ahead of time?
Yes. You can prepare the dashi broth and keep it refrigerated, then reheat it and add tofu, wakame, and dissolved miso shortly before serving. Alternatively, make the full soup and refrigerate it promptly, understanding that the tofu and seaweed will soften. For the freshest texture, keep the miso separate from the broth until reheating, then stir it in off the boil.