"Barbecue Nation," a new exhibit at the Atlanta History Center, takes a deep dive into the history and culture of the South's most-loved food. But barbecue, like the South and the rest of the United States, is increasingly global. So "On Second Thought" is setting out on a series of roadtrips to see how different cultures and countries represented right here in Georgia do barbecue. We started off with a visit to Chama Gaúcha , a Brazilian restaurant in the Buckhead neighborhood of Atlanta.