poeloq posted a couple of photos of a small restaurant / food stall:
It looks like this small restaurant / food stall is serving steamed mantou (steamed buns) or baozi (steamed buns with a filling inside). You can see the stack of bamboo steamers in the picture. There’s a chance that it’s actually steamed jiaozi (dumplings), but it’s much more likely to be mantou / baozi.
For more information on mantou, check out Wikipedia’s entry on the subject.
Anyway, I really like these photos because they capture the subject well. There are thousands of small food stalls like this in Beijing and in other cities across China and they look just like this. Also, I’m a sucker for black and white photos!