Ramen Salad is one of the most famous local dishes in Hokkaido, and is unable to be found on menus in other parts of Japan. A variety of toppings like lettuce or boiled egg are used, served over cold ramen noodles. It is traditionally dressed with sauce immediately prior to eating. At izakaya restaurants in Hokkaido, this is typical fare. It’s also served for school lunches and is a favorite in the home. It’s widely recognized that's its origin is Big Jug, a restaurant, in Sapporo Grand Hotel, created this in 1985 and it since grew in fame. Ramen Salad is different from Hiyashi Chuuka, which is ramen noodles in cold soup or sauce.
The Big Jug’s ramen salad from their website