We know what you're thinking. You saw "Galleria" and imagined meals at Morton's Steakhouse, or Cafe Annie or any number of high-dollar restaurants. That's why Chacho's is a natural choice. Located just down the street from the Galleria in a faux adobe building with bright pastel colors, Chacho's offers first-rate Tex-Mex made with fresh ingredients for paltry sums. As a result, Chacho's gives the House of Pies a run for its money as the best post-2 a.m. eatery for all your sobering-up needs. But it would be folly to arrive after last call. Their margaritas are terrific.