Honestly, if I had 1 meal to enjoy during a layover in Japan I wouldn't "waste" it on Ichiran. But if you go to Kawasaki station you'll have many, many options. You'll arrive at Kawasaki Keikyu so exit and head towards Kawasaki Station (JR). Go into the basement in front/below Kawasaki station and there's a lot of good restaurants with everything you can think of. The shotengai in front of the station (the area where Ichiran is) has a lot of options too. Can't go wrong with Sushi Zanmai for example, which is around the corner from Ichiran. Or go into Kawasaki station and walk over to Lazona, the top 2 floors have a wide selection of restaurants too.

Alternatively, is the only purpose is to grab some food then you might as well get off at Kamata station, lots of restaurants around there too.