My favorite ramen magazine is pretty much 99% Tokyo. Kawasaki city, just a few minutes from the transportation hub of Shinagawa, is actually in Kanagawa prefecture, even though it feels like it could be Tokyo. Luckily, said magazine shares my feeling, and throws in a bone; one excellent shop that is worth the extra few minutes south. A chicken bone, simmered for hours and hours.
San (三), san (三), nana. The above kanji character apparently doesn't exist, but maybe someone with better Japanese skills can enlighten in the comments. Following the theme of 3s, the shop offers 3 menu items.
A ramen and 2 kinds of tsukemen. Almost everyone in the shop was eating the 煮番搾り, a thick bowl of chicken soup, porridge-thick.
Onions in the bowl, onions in the soup, and onions on top.
A dollop of the concentrated, sardine-laced broth finishes it off. The entire package is intense.
Kanagawa, Kawasaki-shi, Kawasaki-ku, Kogawacho 9-7
Closest station: Kawasaki
Open 11:00-15:00, 17:00-23:00
Weekends from 11:00 until the soup is out in the evening