I love Mexican food, and Rosa Mexicano is the absolute best. It was one of my favorite places before I went GF, and after being diagnosed I spoke to the chef in person and he told me that almost EVERYTHING in the restaurant is gluten-free! Even the enchiladas are made from corn and do not contain gluten. He said about the only thing I couldn't have was the chicken quesadilla, though he did suggest I ask my waiter to confirm my menu choices as GF just to be extra-safe.
We had the guacamole to start, which is made fresh at the table and served with GF tortilla chips, and then my entree was the crabmeat (jaiba) enchiladas, which are spicy and fantastic - I get them every time. I also had a pomegranate margarita, which is small for the price but tastes wonderful. I did not have dessert but I believe the flan is GF - but please ask.
It's right in the middle of Atlantic Station so perfect for dinner and movie for a date, or dinner and shopping with girlfriends or Mom. It is a little pricey for a casual dinner at about $20 for an entree, but worth it. Lunch is more reasonable at $10-15 for an entree.
This is my favorite restaurant in Atlanta, and one of the few places I feel truly relaxed and safe about gluten-free. Go!