Sapporo ramen is traced to Aji no Sanpei restaurant in Susukino, which introduced miso-based ramen in 1955; the butter and corn additions became associated with Sapporo ramen in the 1960s–1970s as Hokkaido's agricultural identity was incorporated into the regional ramen character; Sapporo's Ramen Yokocho ('Ramen Alley', established 1951) is a preserved historic alley of ramen shops that became a model for ramen yokocho culture nationally
Sapporo ramen is the defining ramen of Hokkaido and one of Japan's four great regional ramen styles — a miso-based tare, pork or chicken broth, thick wavy noodles, and a final tableside addition of corn and a knob of butter that melts on the surface and enriches the bowl. The development: Sapporo's Susukino district ramen culture traces to the 1950s, when Sapporo ramen shops began combining the city's abundant local dairy production (Hokkaido butter), sweet corn from Hokkaido farms, and local white miso with conventional pork-bone broth. The result is categorically different from Kyushu tonkotsu or Tokyo shoyu: the miso tare is prepared separately and added per bowl (the same tare system as all ramen); the pork-and-chicken broth is lighter than tonkotsu (not boiled to opacity); the miso used is typically white miso or a blend of white and red for different shops; the corn is fresh (summer) or sweet canned corn; the butter — specifically Hokkaido butter, notably from the Yoichi and Tokachi regions — is served as a single large pat placed at the bowl's edge that the diner can optionally stir in. The butter addition is not standard in Sapporo ramen — it is an optional enhancement (optional additions are called 'toppings' in Japanese ramen culture) rather than required.
Miso tare is the identity element — added per bowl at service; pork-chicken broth is the base (lighter than tonkotsu); wavy thick noodles (not straight) hold the rich miso broth; corn is a regional Hokkaido agricultural identity element; butter is optional but iconic; the miso must be dissolved in a small amount of hot broth before adding the full stock to prevent lumping.
Home Sapporo miso ramen: base broth 1L pork stock + 500ml chicken stock; miso tare: 100g white miso + 50g red miso + 2 tbsp mirin + 1 tbsp sake + 1 tbsp sesame oil — combine and refrigerate; per bowl: 3 tablespoons miso tare dissolved in ladle of hot broth, then full broth added; wavy noodles cooked separately; toppings: chashu, corn, menma, nori, spring onion, and optional butter pat; the best Sapporo shops add a wok-fired stir-fry of vegetables (moyashi/bean sprouts, cabbage) directly in the broth before service — a technique called 'ita-su' that adds wok-char flavour.
Using dark hatcho-style miso (too assertive, overpowers the butter and corn); dissolving miso directly in the bowl without pre-diluting (creates lumps); adding butter to the ladle during cooking (cooks the butter prematurely — it should melt from bowl heat at the table); using canned corn without draining thoroughly (excess liquid dilutes the broth).
Ono, Tadashi — Japanese Soul Cooking; Solt, George — The Untold History of Ramen