Sichuan food, from south of Xi'an, is spicy and tingly. But the quickest way to describe the food from our region, Xi'an, is spicy and sour. We really like our rice vinegar. Of course, there are other characteristics, like the use of cumin and lamb, and lots of things made out of flour—like noodles, buns, and flatbreads—that are all part of our identity as well. Xi'an's cuisine is really casual, on-the-go food; there's nothing fancy about it. Most of the spice is in our chili oil—it's always made fresh by my father, who holds the secret recipe for it.