Guy Fieri's always down for a good sandwich, so he's stopping in to check out some of the Triple D Nation's latest creations. A food truck in Nashville put down roots and started churning out cheesy concoctions. A Denver diner's gone global, dishin' up eats from all over the world. A seafood joint in Miami put their signature dish inside two pieces of bread, and as a bonus, Guy's letting us in on a Fieri family tradition in Northern California.