This is my 3rd trip to SF in 18 months and I have yet to give food trucks a try. Typically, I have my dining schedule down pat before arriving, but this time I am hoping to eat on the streets (mixing it up with dine-ins, of course). I will be in the Union Square area from Sunday to Thursday and in Stanford on Monday. Will only have a car on Monday, but will walk anywhere and/or use public transit. Any cuisine will do, just not all mexican. Suggestions?