Ryohei Hayashi, chef at Tenoshima, a Japanese restaurant in Tokyo’s Aoyama neighborhood, has determined the perfect amount of seasoning needed for this recipe based on the weight of the ingredients.

Ryohei Hayashi, owner-chef of Japanese cuisine restaurant Tenoshima in Tokyo, had just returned from a trip to Hokkaido, where he visited an area where makobu kelp grows wild in order to observe ...