This trip, Guy Fieri's digging in to stick-to-your-ribs comfort food. In Atlanta, the down-home joint cooking up righteous chicken and biscuits and house-cured lox. Across town, the twin-brother team firing up Southern grub like brisket burger and chicken-fried ribs. And in Fort Collins, Colo., the funky cafe serving up vegetarian specialties like tomatillo and chickpea pizza and a savory cauliflower steak.