Visiting SF from NYC and looking for Chinese food.
What a quandary - you throw your net far-and-wide with your too-general interest.
Since you have NYC's xlb - we won't lead you to Shanghai Dumpling King or Shanghai House, unless you'd like the salt and pepper pork knuckle at SH? dry fried green beans? dry fried chicken wings? Do you eat seafoods? pork belly? faux meats? hand-pulled noodles? What do you eat at home?
5037 Geary Blvd
(between 14th Ave & 15th Ave)
San Francisco, CA 94118
Old Mandarin Islamic
3132 Vicente St
(between 42nd Ave & 43rd Ave)
San Francisco, CA 94116
Z and Y Restaurant
655 Jackson St
(between Wentworth Pl & Cooper Aly)
San Francisco, CA 94133
and now, for something different:
680 Clay St
(between Montgomery St & Kearny St)
San Francisco, CA 94111
If you like innards, you should consider Spices II szechuan , the blood pork cassarole and similar. Although it's not on the right side of town --- you might end up at Jai Yun or Z and Y, which are closer (good recs by Cynsa)
Or, closer to the ballpark, get a table at Incanto - italian, focusing on innards of the highest quality. Great little place, modern northern italian, star chef. Known for their tuna heart pasta, but get whatever's on special, too. Good wine list. I had a really tasty brain there.
Spices II is on 6th and Clement and differs from Spices I on 8th and Clement that Cynsa tells you has Stinky Tofu.
Spices II has by my standards excellent Sichuan and the closest (particular the ma po tofu) to what you find in Chengdu and better than Sichuan we found in Taipei.
Other favorite (also a favorite of many Beijing ex-pats) is Beijing Restaurant out on Alemany and Ocean. This was Yao Ming's favorite place when he was in town. Excellent Beijing pancakes, cumin lamb, pickled veggie fish soup, and another great version of the extremely spicy chili delight (conceptually like moo she pork, but totally different, that Old Mandarin Islamic also has under a different name). After 10:30 until 2 AM they have Beijing street food items like MaLa Tang (soup) where you can chose your ingredients and selections of various grilled skewers.
Both these places require public transit and some walking or a car, but are worth it.
Also, in Chinatown on Pacific just west of Stockton is Dol Ho, low priced small little dim sum place filled with old men reading their papers. Feels just like Hong Kong and the quality is generally good. Excellent chili sauce in little jars on every table, which must be home made. Recommended lunch stop. Unknown to tourists.
re: Thomas Nash
re: Melanie Wong
Oh! Next time I will buy a jar.
It doesn't last long at the tables. Between me and an elderly Chinese couple the other day, 3/4 of a table jar disappeared in a few minutes.
Also good for home use, coming from the other end of the dim sum pricing spectrum, are the X0 and regular sauces from Yank Sing, available at all Asian Markets and at Yank Sing itself.