This is a fine Vietnamese restaurant and a popular one. They in fact have two locations: one in Chinatown (Spadina) and another near by on Bloor across from the ROM.
The smiling bull of their logo is both welcoming and funny. I wish they sold t-shirts. The name translates as "Hung's Soup". And the soups here are top-notch. Not only are they good-tasting, but they come with a platter of crunchy bean sprouts, basil sprigs, and lime wedges. And you know when I say soup that's really an understatement. What you get is a cauldron of tasty broth, noodles, vegetables and/or meats (depending on what you ordered).
I'd also recommend the vermicelli dishes; they are light yet filling, and incredibly tasty. They come with a base layer of fresh vegetables in a gentle vinegar dressing, then a layer of rice vermicelli, and topped off with either grilled chicken or deliciously fragrant beef.
Popular with the 20 something crowd, the place is almost always full of energy. Oh, try the non-alcoholic fruit drinks/shakes, and of course you can't miss out on the green tea!
They do good take-out too. They package stuff quite well, so it stays fresh.