Better known to the world at large as miso soup, miso shiru is a ubiquitous part of Japanese cuisine. Served at very top-end and most down-home establishments alike, offered alongside in-flight meals aboard Japanese airlines, sold at supermarkets in various instant forms (since 1974), and generally disseminated throughout the country, miso shiru is, in every sense of the word, a staple.
Beyond the usual suspects found swimming in the soup — wakame, cubes of kinu (silken) tofu, thin strips of abura-age (deep-fried tofu) and sliced negi (scallions) — a wealth of variety exists and not only in these accoutrements. Dozens upon dozens of prized regional forms exist: Hatcho miso, hailing from Okazaki, Aichi Prefecture; light, white Shinshu miso originating in Nagano Prefecture; and Tokyo’s own ama (sweet) miso, just to name a few. Different ways of serving the soup also abound, with dishes ranging from hiyajiru, a chilled preparation native to Miyazaki Prefecture, to the hearty, veggie-packed kenchinjiru, a gift from shо̄jin ryо̄ri (Buddhist vegetarian cuisine).
The origins of miso are as hazy as the soup itself. On one hand, archaeological traces of salt-preserved pastes in Japan have dated miso-adjacent foodstuffs to the late Jomon Period (10,000-200 B.C.), but these once-edible artifacts are perhaps too distant to be an ancestor of miso proper.