Hsu’s answer for re-creating the magic of a ryokan, a Japanese inn, is to travel this summer to SingleThread Farms in Healdsburg, Calif., to stay in one of its five rooms and dine at its Hokkaido-inspired restaurant, Usu-Zan. An alternative farther south in Malibu, Calif., there is the 16-room Nobu Ryokan, complete with tatami mats and teak soaking tubs.