Imoni

Yamagata's autumn riverbank stew of taro, beef, konnyaku and spring onion simmered in soy and sake over a driftwood fire

Origin: Yamagata & the Japanese Archipelago

From the journey of Taro.

Imoni means, plainly, taro boiled, and the dish is straightforward: satoimo, thinly sliced beef, konnyaku, mushrooms, and spring onion simmered in a broth of dashi, soy sauce, sake, and sugar. What makes it worth an entry is not the recipe but the occasion. Across the Tōhoku region the imonikai is an autumn institution, an outdoor gathering on a riverbank at which the pot is set over a fire of driftwood and everyone present cooks and eats together as the weather turns. Yamagata City takes this to an extreme that has to be described to be believed. The Nihon-ichi Imonikai, held each September on the banks of the Mamigasaki river, cooks for tens of thousands of people in a single cast-iron cauldron six metres across. It is filled and stirred by a construction crane fitted with a purpose-built shovel, the sake goes in by the cask, and the firewood is measured in tonnes. The absurdity of the scale is the entire charm of it, and the festival has been running since 1989. There is a genuine and quite serious regional dispute underneath the fun. Yamagata's imoni is beef, seasoned with soy sauce. Miyagi's, across the mountains, is pork, seasoned with miso. Each side regards the other's as an error, the argument is conducted with real feeling every autumn, and neither will concede. The atlas does not award it: the version given here is the Yamagata one, and the Miyagi one is a different and equally defensible dish. The taro is the constant in both. Satoimo, the village tuber, was in Japan before rice was, and it remains the offering at the harvest moon and a fixture of New Year ozōni. Imoni is what happens when that ancient autumn vegetable meets a riverbank, a large pot, and a reason to gather.

Ingredients

Stew

  • 800 g satoimo (taro), peeled
  • 400 g thinly sliced beef, such as sukiyaki cut
  • 1 block konnyaku, torn into bite-sized pieces
  • 200 g maitake or shimeji mushrooms, pulled apart
  • 4 spring onions, cut into 4cm lengths

Broth

  • 1.2 litres dashi
  • 100 ml soy sauce
  • 100 ml sake
  • 2 tbsp mirin
  • 1.5 tbsp caster sugar

Method

  1. Peel the satoimo. The sap makes hands itch fiercely, so wear gloves, and peel them dry rather than wet since wet taro is impossible to grip.
  2. Cut any large corms in half so all the pieces are of a size, then rub them with a teaspoon of salt and rinse. This draws off some of the surface slipperiness.
  3. Parboil the taro in plenty of water for five minutes, then drain and rinse. Discarding this water takes both slime and a good deal of the oxalate with it.
  4. Tear the konnyaku into pieces rather than cutting it. The ragged surfaces hold the broth, which a knife-cut face does not.
  5. Parboil the konnyaku for two minutes and drain it, which removes its faint lime smell.
  6. Bring the dashi, soy, sake, mirin, and sugar to a simmer in a wide heavy pot.
  7. Add the taro and konnyaku and simmer, uncovered, for fifteen minutes until the taro is tender to a skewer.
  8. Add the mushrooms and simmer for five minutes more.
  9. Separate the beef slices and add them a few at a time so they do not clump, skimming the surface as it foams. Two or three minutes is enough.
  10. Add the spring onions, cook for a further minute, and take the pot straight off the heat. Serve directly from it into bowls, with rice and pickles.
  11. Traditionally, once the stew is finished, the leftover broth is thickened with udon or with curry roux for a second course. Nobody wastes an imoni broth.

Notes

Satoimo is sold fresh and frozen by Japanese and Chinese grocers, and frozen peeled corms save the worst of the handling. Peel it dry and wear gloves: the sap causes fierce itching, and a wet corm is too slippery to hold safely. The salt rub and the parboil are both standard Japanese practice and both matter, since they take away the sliminess that otherwise clouds the broth. Use a good dashi rather than granules if you can, as the broth is thin and there is nowhere for a poor one to hide. Miyagi cooks make this with pork and miso instead of beef and soy, which is a different dish and is not a mistake.

The Gastrographer

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