Sobayu, the pot of cloudy water that ends a soba meal

At a soba shop in Japan, the meal does not end when the noodles are gone. A few minutes later a small lacquer pot arrives at the table, unordered and unexplained, full of hot cloudy water.

What is in the pot

This is sobayu (そば湯), the water the noodles were boiled in. It is pale, slightly thick with starch, and tastes quietly of buckwheat. The pot, usually square with a short spout and finished in red or black lacquer, is called a yutō (湯桶).

How to drink it

Sobayu follows cold noodles: zaru or seiro, served on a bamboo tray with a cup of dark dipping sauce called tsuyu. Pour the hot water into whatever sauce remains in the cup, roughly one part sauce to two or three of water, and drink it as a broth. Leftover spring onion or wasabi can go in too.

It is free, and nobody measures how much you take. If the pot does not appear, a short request is enough: sobayu o onegai shimasu.

そば湯をお願いします。

Why it changes by region and by hour

The habit is usually traced to Shinshu, today's Nagano, mountain country where buckwheat grows more willingly than rice. In Tokyo, where the dipping sauce is darker and saltier, the cup takes more water before it becomes drinkable.

The pot also changes through the day. At an 11:30 opening the water is thin and nearly clear; by two in the afternoon, after a full lunch service, it pours like a light soup. Some shops whisk in extra buckwheat flour so that it is thick from the first customer.

Finishing the cup is the nearest thing a soba shop has to dessert. Set the lid back on the pot, and the table is done.