Miso soup is a traditional Japanese soup made by mixing softened miso paste into a dashi stock. Dashi is a basic Japanese soup stock made with dried bonito flakes, kelp, and anchovy. Miso paste is made from fermented soybeans, grains (steamed rice or barley), salt, and koji culture (a fermentation starter) . The soup can be customized with various optional ingredients, such as vegetables, tofu, and seaweed, depending on regional and seasonal recipes and personal preference. Miso soup is considered one of the two basic soup types of Japanese cuisine, along with suimono.

To make miso soup, the basic steps are to prepare the dashi stock, dissolve the miso paste in the stock, and add any desired ingredients. Homemade miso soup is easy to prepare and can be made with various ingredients besides tofu and wakame seaweed, such as root vegetables, leafy vegetables, and mushrooms. Instant miso soup is also available in single-serving packets, which generally contain dried toppings such as wakame and tofu with soybeans that reconstitute rapidly on the addition of hot water.

Miso soup is not only delicious but also brings many great health benefits. The natural chemical compounds in miso, such as Vitamin K2, linoleic acid, and saponin, are known to reduce the risk of heart disease and lower cholesterol. However, instant miso soup tends to contain higher sodium and may not be as good as homemade miso soup.