Shanghainese love
doujiang (soy milk/soy milk soup) at breakfast. There's a sweet version which is served either hot or cold. The cold version is ubiquitous in its grab-and-go transparent plastic cups; you usually have the hot version at sit-down places, but it's still just plain soy milk with some sugar added. Who likes that? (Well, a lot of people, apparently.)
The savory version is something else; properly done, it's a masterpiece and food for the gods, IMHO. It's hot soy milk to which has been added vinegar or some other sour matter to curdle it (surprisingly, soybean milk curdles much like cow's milk) and salt and/or a salty agent (the best versions will have brine shrimp in it). Chili oil is usually also present, so with the salty, sour, and spicy combination you'd need only have to add a little sugar to make "Strange Taste Doujiang" but I don't think I would like that. Beyond the above ingredients, other vegetable matter such as scallion tops may be added, and it's sometimes served with a bit of
Nori-type seaweed on top. The other indispensable ingredient is slices or broken pieces of
you tiao, the Chinese cruller, floating on top. (It's a good thing the do with stale
you tiao.)
When I'm in Shanghai I crave savory
doujiang for breakfast, and my wife's experience and intuition is`usually successful at tracking down a good version. On my last trip , however, I did a lot of early morning foraging by myeslf, and found it difficult to communicate that I wanted savory
doujiang. My attempted Mandarin or Shanghainese request usually resulted in shrugged shoulders or in my getting
sweet doujiang (yuck!)
Finally I asked my wife for help. "Simple," she said. "Just ask for 'A-jiang'" (with an "A" as if speaking the name of the English letter "A"). The next time out I found it worked like a charm. My wife then pointed out that if you order "B-jiang" in Shanghai you'll get plain soy milk, and if you ask for "D-jiang" you'll get the sweet version. There apparently is no "C-jiang", not even a "Gentleman's C-jiang" but apart from that I approve of this grading system; I'd give a good version of savory
doujiang an "A" any day, and a sweet version a "D" (if not an "F").