Second on Z&Y. My favorites were the spicy numbing pig tongue (cold appetizer), "spicy beef and chicken with flaming chile oil," "Yunnan ZhangYi chicken with explosive chili pepper," braised green pepper (jalapeño), and tan dan noodles.
Z & Y
655 Jackson St, San Francisco, CA 94133
If you are willing to try something a little out of the ordinary go to Jai Yun. It is Shanghai Chinese and presented as a tasting menu, from $45-100 per person. When we were last there about three weeks ago the $45 menu had 11 cold and 7 hot dishes. (I may be off by plus/minus one dish.) Some of them I couldn't identify but they all ranged from good to outstanding.
680 Clay St, San Francisco, CA 94111