Went to Canteen on Friday night with my wife. We got there around 9:30 and were seated at the only open table (there were also bar seats available). Very enjoyable experience. There is a limited menu - just 4 appetizers and 4 entrees - but I would happily eat anything that the chef wanted to make.
We shared 2 appetizers. One was a scallop ceviche - small pieces of chopped up scallop mixed with some citrus juice and hot peppers, then re-assembled atop their gorgeous shells. These were the freshest, most scallop-flavored scallops I have ever had in the bay area - it seemed like they were alive moments ago. The other appetizer was a compilation of vegetables, some raw, some cooked, all shaved thin and topped with a mint vinaigrette. My wife declared this the dish of the night - and I concurred. Great mix of asparagus )I think green and white), summer squash, and the occasional shaving of cucumber. Everything looked the same (especially after being coated with a brigth green but mild sauce) but the variety of textures and flavors was stunning. And there was a small dollop of some type of citrus granita do deliver a little extra sweet and tart note. Very creative, but made total sense as a dish. The other optiosn were an avocado-mint soup and a lamb dish.
The entrees were also quite good. I preferred the vegetarian dish - sauteed wild mushrooms on a corn clafouti with finely diced beets. Good variety of mushrooms - including lots of clamshells - sitting on top of a wonderfully light corn cake that tasted of an intense corniness despite being so fluffy. Our other dish was broiled tuna loin with green beans - again the meat was amazingly fresh and tender, but this dish was the least interesting we had. The other entree choices were steak tartare and blanquette de veau (I almost had to abandon my no-red-meat-eating wife to eat the veal all by myself...)
Dessert was stewed apricots with pistachio cake, which was great. Service was friendly and very capable, though I wonder how it would be maintained were it more busy / full - there was just one waiter and two chefs, which worked great for having 10-12 people in there, but when all 20 seats are full and people are waiting it might be a bit of a zoo. Very interesting wine list, all priced below ~$50, all available by the glass.
I have no idea how often the menu turns over. If it turns over frequently, I would happily become a regular. No reservations. They do serve breakfast and lunch, though the breakfast menu looked more standard than interesting.