I had a bit of trouble deciding which English translation to give for the name of this dish. One possible name is "sweet and sour Chinese cabbage", but none of the characters in the Chinese name actually mean "sweet", plus (at least to the British ear) the phrase "sweet and sour" in connection with Chinese food generally conjures up images of terrifyingly red gloopy sauces. The version above is one I ate at Le Wei Xiang in Lewisham, where it was simply listed as "fried Chinese leaves in vinegar". However, in the end I decided to go with the name that Jennifer Miller gives in her beautifully-illustrated post on ordering leafy greens in Chinese restaurants — vinegar-glazed Chinese cabbage.
The Chinese name is 醋溜白菜 (cù liù bái cài). 醋 means "vinegar", and I've already covered 白菜 at some length. 溜 confuses me a little. I've seen it in the names of various other dishes too (e.g. 溜肚片/liù dǔ piàn, which is stir-fried sliced tripe), but CantoDict tells me it means either "slippery" or "rapids" (as in rapidly-flowing water). My paper dictionary says the former meaning is pronounced liū and the latter liù — neither meaning really makes that much sense to me in the context of this dish, so I may be transliterating it wrong. I can't actually remember why I had it down in my notes as liù rather than liū!
醋溜白菜 is a dish that really showcases how well-suited Chinese cookery methods are to vegetables such as leafy greens. Also, it's not only vegetarian, but actually vegan. There are a few variations on the theme, but the basic recipe involves stirfrying the chopped cabbage before adding a simple vinegar/salt/sugar sauce and cooking it down until the cabbage is tender yet still crunchy, and the sauce has reduced to a flavourful glaze. If you want it spicier, you can flavour the initial stirfrying oil with a few dried chillies and/or Sichuan peppercorns, or just add some ground Sichuan pepper at the end of cooking. You could also include a few pieces of carrot for extra colour contrast.
I couldn't find any English-language recipes for 醋溜白菜 on the internet (though I have found some since; see below), but Jennifer was kind enough to translate one of the many Chinese-language recipes available, and send her translation to me to try out and post here. The notes in brackets below are hers, not mine.
When I tried this, I left out the MSG (since I didn't have any), and I cut the cabbage as shown in this video. I also used more green onion (spring onion) than it says to in the recipe, because according to my scales 5g is less than half of a spring onion, so I just used the whole thing.
Regarding regionality, Jennifer notes that this is probably a more northern dish than a southern one, "because of the use of bai cai and vinegar, plus the general heartiness of the dish. I couldn't see it coming from the eastern provinces south of Shanghai because those places tend to serve more delicately-flavoured dishes." However, she wants me to point out that this is just coming from her own personal experience, not from any sort of formal research, so if anyone has any opinions on this then we'd both be happy to hear them!
Update, April 2011: Sunflower Food Galore now has a recipe for this dish; Sunflower says that it's from Shandong, a province on the east coast of China which is famous for its vinegar.
Update, May 2011: I've also found a recipe by Savour Asia which uses a different type of cabbage, but it's still the same dish.