Miso soup is traditionally served as a breakfast food in Japan. Mornings being a busy time in any culture, this easy soup only has a few components and comes together in under ten minutes.
It’s also one of the few dishes that even the most domestically illiterate Japanese bachelors can make without a recipe. That’s because there are only three things that go into the soup: dashi, gu (I’ll explain later), and miso.
Dashi is the Japanese word for stock. Modifiers are used with the term dashi to refer to specific types, such as chicken dashi and shiitake dashi, but when the word is used by itself, it almost always refers to a very basic stock made with konbu (kelp) and dried shaved bonito (katsuoubushi). It’s used in many Japanese dishes and is the core component of miso soup. I often see miso soup recipes in English that don’t include any dashi. This is akin to making chicken soup without any chicken.
These days, most people use instant dashi granules, but like bouillon cubes, instant dashi is an MSG laden processed food that’s a poor substitute for making dashi from scratch. Unlike chicken stock though, making dashi from scratch does not entail hours of simmering and can be made in a matter of minutes.
Gu, which roughly translates to “stuff”, can basically be anything your heart desires. This often entails chopping up odds and ends from the vegetable drawer, or tossing in veggies from dinner the night before.
Personally I like my miso soup slightly sweet, so I tend to start with root vegetables like sweet potatoes, carrots, and onions. Then you add ingredients in that take progressively less time to cook such as mushrooms, tofu, seaweed and leafy vegetables.
The last component of miso soup is of course the miso. Miso is a paste made by fermenting soy beans and salt along with rice or barley using a type of mold called koji. Thanks to the Maillard Reaction that occurs during fermentation, these humble legumes and grains are transformed into a flavorful paste with deep earthy notes and a meat-like savoriness. Depending on the ingredients, technique and length of fermentation, the resulting miso can be anywhere from creamy white to earthy red, to coffee brown, with flavor profiles as varied as the colors.
Unlike other East Asian soups where fermented bean pastes are often boiled in the soup, miso soup should never be boiled once the miso is added. Some people claim this retains the live probiotics present in the miso. I have my doubts about the probiotic claim, but boiling the soup destroys the nuanced flavors and aromas in high quality miso, which is why it’s best to add the miso off the heat. Boiled miso soup also has a tendency to separate, making it necessary to stir your soup every time you take a sip.
Because there’s a lot of room for improvisation and because the concentration of salt in miso varies by brand, this is one of those dishes that’s best prepared without a recipe. You just need to know a few basics, which I’ve outlined below:
The preparation of dashi will depend on whether you’re using granules, packs, or the raw ingredients. While it’s best to make dashi from scratch, dashi packs make for a decent compromise. They’re essentially giant tea bags that hold ground konbu and dried fish. If you’re vegetarian, you can make a stock using konbu and shiitake mushrooms. For more information, see my post on the different types of dashi.
Once you’ve prepared your dashi, you just need to add and cook the stuff you want in your soup. Usually this means triaging the ingredients by the amount of time each one takes to cook. I’ve listed some examples below, but there are really no rules around what kinds of gu can or can’t be added.
Hard Vegetables: Root vegetables and hard squashes take a bit of time to cook, which is why they go in first. Sweet potatoes, carrots, onions, daikon, kabocha pumpkin, and butternut squash are all delicious additions to miso soup.
Tofu Products: Tofu, aburaage (thin fried tofu), atsuage (thick fried tofu), ganmodoki (tofu fritter), and yuba (soy skin) are all examples of soy products that can be added.
Mushrooms: Mushrooms such as maitake, shiitake, enoki, shimeji and eryngi not only add wonderful texture to the soup, they can also enhance the dashi by contributing flavor.
Vegetables: Hard leaf vegetables such as kale, cabbage, napa cabbage, and bok choy, as well as other vegetables such as snap peas, green beans and turnips don’t take a long time to cook which is why they go in towards the end.
Seaweed: Seaweed such as wakame, funori and aonori are added towards the very end as well. If the seaweed you use is dried, be sure to rehydrate it first in water. If the seaweed you use is salted, be sure to rinse it in plenty of fresh water to remove the salt first.
Leaf vegetables: Just before you turn off the heat to add the miso, add tender leafy greens such as spinach, water cress, scallions, chives, etc.
I often get asked what the best type of miso is for making miso soup. The answer mostly depends on the region of Japan the cook comes from. Generally speaking, the Kanto region (the area around Tokyo) uses akamiso (red miso), whereas the Kansai region (the area around Osaka) uses shiromiso (white miso). But then there are regional anomalies such as Aichi prefecture that uses hatchōmiso (a dark, almost black miso), and Kyoto, which uses a mild white miso that is very sweet.
Because different types of miso have varying concentrations of salt, it’s impossible to give you an exact measure of miso for the amount of dashi. That said, start with about 1 tablespoon of miso for every 1 cup of dashi, adding more if necessary.
One thing to look out for is that some miso sold in the US already includes dashi concentrate, which almost always means it’s also loaded with MSG. Ingredient labels should always have English translations, so be sure to read the label and make sure you’re not getting miso with unnecessary additives.
Marc Matsumoto is a culinary consultant and recipe repairman who shares his passion for good food through his website norecipes.com. For Marc, food is a life long journey of exploration, discovery and experimentation and he shares his escapades through his blog in the hopes that he inspires others to find their own culinary adventures. Marc’s been featured in the New York Times, Wall Street Journal, and USA Today, and has made multiple appearances on NPR and the Food Network.