Order iekei ramen at the shop that invented it, and say the three words
The head temple of a ramen genre
Iekei ramen is pork-bone and soy broth with chicken oil, thick straight noodles, spinach and nori. It was invented in 1974 by Yoshimura Minoru, a long-haul trucker who fused Kyushu tonkotsu with Kantō shōyu ramen. Yoshimuraya is the sōhonzan, the head temple, of the style.
Why it's unique
Iekei is now a national genre with well over a thousand shops, and there is exactly one shop where it started. Yoshimuraya is that shop, and the head of a formal lineage that still decides who may call themselves its students.
The lineage is taken seriously. Shops that trained under Yoshimura and received formal noren-wake are called chokkei, direct lineage, and there are only around thirteen of them nationally. One was excommunicated in 2011 for switching to house-made noodles. Eating at the head shop is eating the reference bowl that every copy is measured against.
Before you go
At the ticket machine you set three things: noodle firmness, broth strength and oil volume. The resident order is "katame, koime, ōme" (firm, strong, extra oil). First-timers should say "zenbu futsū" instead, because full strength is genuinely heavy. Order rice as well, pull the three sheets of nori out of the broth before they dissolve, let them soften, then wrap rice in them and eat it as a hand roll. Use the table garlic, vinegar and chilli-bean paste halfway through as ajihen, a flavour change, rather than grinding out the soup.
To tell a genuine direct-lineage shop from a copy, look for Sakai Seimen noodles, smoked chāshū, a bold soy tare and black bowls. The "-ya" suffix proves nothing on its own: Rokkakuya is not chokkei, and neither are the big chains. Sugitaya in Shin-Sugita, opened 1999, was the first officially recognised direct-lineage shop and sits near the 1974 birthplace.