Spicy mango margarita on happy hour! It's the best thing they've got.
I always get the chicken burrito with a wheat tortilla and black beans, with the rice on the side. They give you a generous portion and I'm able to add as much or as little as I want to my burrito, depending on how hungry I am.
Their happy hour is great, and they have an awesome range of margaritas and beers.
I also have to say that they are SUPER willing to help you plan an event. They've offered to set aside the patio for a large party, and they really seem to take the time to help you without being difficult. I never felt like I was an inconvenience to make requests of them. They have wonderful customer service.
Get there early on Friday/Saturdays, because it WILL fill up. The food is great for the price and quality.
Also, try the taco sauce on the salsa bar. It's spicy, but SO GOOD.