In a small bowl, combine the first 5 ingredients. Cut into bread to make 1-in.-thick slices, but don't cut all the way through—leave slices attached at the bottom. Spread cheese mixture between the slices.
Wrap loaf in a large piece of heavy-duty foil (about 28x18 in.); fold foil around bread and seal tightly. Bake at 350° until heated through, about 20 minutes. Serve warm.