Dojō — the little freshwater loach — was Edo's protein of the people: cheap, sweet, cooked in shallow pans with burdock and heaps of scallion. Asakusa once had dozens of specialist houses; a handful remain, and Iidaya, established 1902 with roots in a Keiō-era rice shop, is the connoisseur's pick — the one where the novelist Kafū Nagai kept his seat, where a doorman still receives your shoes (a house rule: "the master's job is the broth and the front door"), and where the sweet-soy warishita is known, by family law, to exactly one person per generation.
What you eat
Whole loach or boneless, simmered tableside in that secret broth, buried — the staff will insist — under an entire box of scallions, dusted with sanshō from the Yagenbori shop that has ground it since the 17th century. The kinder gateway is yanagawa: boneless loach and burdock bound in egg. Eel, catfish in winter, and the okami's own one-secret nuta fill out a menu that has not chased a trend in fifty years.
The Noren View
At around ¥5,000 for a full evening, this is living Edo food culture at the price of a chain izakaya — with 180 seats, an English menu, and genuine warmth toward foreigners. Come after Kappabashi's knife-shopping lanes next door, sit on the tatami, and eat what the carpenters of this city ate for three centuries.
Who should go
Curious eaters ready to go one dish deeper than sushi; Kappabashi pilgrims; anyone who believes the humblest specialties keep the oldest secrets.