This is a delicious, simple, ginger-toned egg, scallion, and cabbage filling for steamed buns. With a little adjustment, it can also make an excellent stirfry to be served with da mien (flat noodles) or rice. See my steamed bun recipes for their ideal setting, though. Oddly, I found these in Beijing, never in Shanghai.
NOTE: This recipe is not terribly healthy as written, since it's a real Chinese stirfry, but just replace oil with spray and use egg whites to be a wimpy westener.