Sanmamen: Yokohama's bean-sprout noodle soup, and how to order it

Overview

Sanmamen is a bowl of soy-seasoned noodle soup crowned with a glossy, starch-thickened stir-fry of vegetables — above all bean sprouts — and thin ribbons of pork. It was invented in Yokohama’s Chinatown in the early Showa years, in the 1930s, by the city’s Chinese cooks, and it belongs to Yokohama in a way that is easy to miss because it is now eaten across the whole of Kanagawa, the surrounding prefecture, where it counts as an everyday staple. It is genuinely this city’s dish; it simply outgrew the district that made it.

The first thing to clear up is the name, because it misleads every English speaker and a good many Japanese ones. It has nothing to do with fish. The autumn saury, sanma, is a different word that merely sounds the same; there is no saury in the bowl and never was. The dish’s name comes from Chinese — most likely a phrase in the Cantonese of the early Chinatown cooks meaning something like “fresh, crisp topping piled on” — and the exact characters behind it are debated. What everyone agrees on is what the name is pointing at: the crunch of just-cooked vegetables, which is the whole idea of the dish and the thing a bad version gets wrong.

The topping is bound in an ankake — a translucent sauce thickened with potato starch — so it sits on the noodles as a hot, glossy blanket rather than sinking in. That blanket traps the heat, which matters more than it sounds and comes up again below.

What to order

You order it by name: sanmamen. Most bowls arrive with a soy base, the standard and the one to default to; some places also offer a salt (shio) version, lighter and cleaner, which is a fair choice if you want the vegetables to read more clearly. The noodles beneath are the thin, springy Chinese noodles, not the thick straight noodle of the city’s other famous bowl.

What defines the dish is the topping, and it is worth knowing what should be in it: bean sprouts as the backbone, then cabbage, garlic chives or leek, a little carrot for colour, slivers of pork, and often wood-ear mushroom, all flash-cooked and folded into the starchy sauce. The vegetables should still have bite. If they arrive stewed soft, the kitchen has missed the point of its own dish.

Two neighbours are worth being able to tell apart when you read a menu:

• moyashi soba — literally “bean-sprout noodles”. Close cousin, sometimes the same thing under another name, sometimes a plainer version without the thickened sauce. If you want the ankake, say sanmamen.
• chanpon — a heartier noodle soup with a milky broth and a bigger pile of seafood and pork. It comes from the far west of the country, not from here, and it is a different dish despite the family resemblance.

This is a bowl to eat in an ordinary neighbourhood Chinese diner — the plain, counter-and-tables places locals call machi-chūka — far more than in Chinatown’s grand banquet restaurants. It is home cooking, and it tastes most like itself where it is treated that way.

What to avoid

The dish’s own name is the first trap, and it is worth repeating because signage plays on it: a menu photograph or an English gloss that promises fish is either a mistranslation or a different dish entirely. There is no saury here.

Watch the bean sprouts, because they are the honest test. In a good sanmamen they are barely cooked, still pale and snapping; in a tired one they are grey, limp and waterlogged, which usually means the topping was cooked long in advance and reheated to order. The ankake hides a multitude of sins visually — everything under a glossy sauce looks fresh — so judge by the crunch, not the shine.

Be a little wary, too, of ordering it in the most tourist-facing corners of Chinatown, where the kitchens are built for banquet menus and dim sum rather than for a single humble bowl of noodles. The dish is not bad there, but it is not the room’s priority, and a diner two streets back that makes it fifty times a day will almost always make it better. This is one case where a plain shopfront is the reassuring sign.

Practicalities

A bowl runs to roughly ¥700 to ¥1,000, which places it firmly as a light lunch or a cheap, warming meal rather than an occasion; a price much above that usually means you are in a sit-down restaurant charging for the tablecloth, not for a better bowl. It is eaten at any hour a Chinese diner is open, and it comes into its own in cold weather — the thickened sauce is a cold-day dish by design, which is part of why it caught on in a port city with raw winter winds off the bay.

The one genuinely useful warning is about that ankake. The starch-thickened sauce holds heat far longer than an ordinary broth, and the first spoonful can scald you well after the bowl has stopped steaming, because the steam that would normally warn you is sealed under the sauce. Give it a minute more than instinct says, and stir the topping down into the soup to let it cool before the first mouthful.

Carry a little cash. The neighbourhood diners that make the best version are exactly the small, long-running places most likely to be cash-only, even as the larger restaurants and the trains have moved on to cards and phones.