He moved to a house in Westchester in upstate New York, an hour’s drive from his childhood home on Long Island, opening an outpost of Ivan Ramen, now closed, in a midtown Manhattan market.

One of Japan’s most popular ramen bars, Mensho Tokyo, is expanding to Los Angeles with a location in Culver City. Founded in 2005 by ramen master Tomoharu Shono, Mensho Tokyo has grown to over 20 ...