. . . coming in for the Texas game. As a native central-Texan, I offer the following:
1) The official foods of Texas are BBQ, Tex Mex, chicken fried steak, hamburgers, and fried catfish. I highly recommend knocking off at least one of each while you are here in Texas. This can be accomplished in a single day.
2) For BBQ, pigs are great for breakfast and Christmas, but brisket is king. The traditional Texas BBQ plate is brisket, polish sausage, potato salad (mustard-based), and beans. Also, it's considered poor form to eat your BBQ with utensils.
3) For Tex Mex, fajitas are native to Texas, as is carne guisada. I recommend both. Carne guisada is something you really don't see much outside of Texas, so try it while you're here. The true test of a Texamex joint, though, is its enchiladas.
4) When you order a soda water, it's all Coke. So don't be surprised if you actually order a "coke," and your waitress asks you, "what kind?"
5) It's a disputed issue, but some authorities consider the birthplace of the hamburger to be Texas (
http://www.texasmonthly.com/story/world%E2%80%99s-first-hamburger). Hamburgers are plentiful in Austin, and there are some great ones out there. The Black Sheep Lodge is one of them. Despite its ranking, Cover 3 is not.
6) Since I have rarely found quality chicken fried steak or fried catfish outside of Texas (as opposed to being able to find quality BBQ and hamburgers in almost any state), I recommend trying at least one of these while you're here. Chicken fried steak for breakfast is awesome.
7) For the love of everything holy, pass on the chain restaurants.