Imoni: Yamagata's Taro Stew and Its Giant Autumn Cook-Offs

Imoni is a stew built around satoimo, taro root that becomes creamy and slightly starchy as it simmers, combined with beef, konjac, and green onion in a soy-flavored broth in the Yamagata city-area version, though a miso-and-pork version is more common on the prefecture's coastal Shonai side, and locals will debate which is more authentic. It's a straightforward home-style dish on paper, but in Yamagata it's inseparable from a specific autumn social custom rather than just something eaten indoors.

The defining custom is imoni-kai, autumn gatherings where groups, coworkers, families, friends, students, cook imoni together outdoors, often riverside, in large pots over an open fire, treating it as much as a social outing as a meal. Yamagata City holds a well-known giant version of this each autumn using an enormous crane-stirred pot to feed thousands, though exact dates and scale change year to year, so check current details if timing a trip around it. The custom generally runs through the fall harvest season as taro comes into season.