Toss 1 1/2 cups shredded rotisserie chicken with 3 tablespoons Buffalo wing sauce. Slice off the top rind of a small wheel of brie. Place on a sheet of nonstick foil; top with the chicken and 1 tablespoon diced celery. Bring the edges of the foil together and seal, leaving room in the packet. Grill over medium-low heat until the cheese is soft, about 8 minutes. Unwrap and top with blue cheese dressing and sliced scallions. Serve with crackers.