I'm not sure if there is really a shop in Hokkaido called Shinya. But the lady said that the chef had a restaurant up there and was doing this pop-up at Meidi-ya's Great World outlet through next Wednesday. It's at the end of the strip of food stalls where Nishiyama used to be.
Hokkaido Dosanko Plaza is a new food hall by Meidi-Ya in Great Word City. There is also Food Plaza which offers ramen, gyoza, bento sets and desserts.
