Mamacita's on NASA Road was great for my alumni function in March 2006. We had a group of about 35 in the restaurant's upper room.
Two things to be aware of if you're planning a program for your group event: Roaming mariachi band, and don't arrive TOO early. I was there 90 minutes early, standard for our events, but the room wasn't ready for me until about 45 minutes prior to the event. And the live music added a challenge for communicating the message to our folks.
Beyond that, though, Mamacita's has great food, a great atmosphere and my alumni loved the margaritas!
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