I searched the board to see if anyone has mentioned Juan's Hacienda on the southwest corner of Preston and Frankfurt, but no dice so I'm talking about it here.
I love this place. They do Tex-Mex standards, and by my estimation, do them better than anyone else. I've followed them from the other side of Frankfurt to their location in Plano to where they are now. Every time I try another Tex-Mex restaurant I leave disappointed.
First, excellent chips and salsa. I have to really watch myself to ensure I don't gorge and ruin dinner. The salsa is warm and blended (although it varies in heat level) and the chips really thin and crispy.
I almost always order the tacos, as they have the best tacos I've ever eaten. They're unbelievably silky and spiced perfectly.
My mom's favorite dish is the Del Rio platter: a sour cream chicken enchilada, beef enchilada, beef taco, and guacamole chalupa, along with rice and beans.
I've had their combination fajitas, and they were also tasty. The chicken used in their enchiladas is also incredibly good - super juicy and falling apart. Great refried beans, as well.
The one dish that we've tried that just really didn't work was a tilapia special. It had a weird sauce and was rather dry. I don't think I would bother with their specials.
I lived in DC for three years, and when I would visit home I would stop in and order a large container of taco meat and a large container of salsa. I then froze both into smaller packages and flew back with them - I couldn't satisfy my craving any other way.