PREHEAT barbecue to medium heat. Add 4 boneless skinless chicken breasts (about 1-1/4 lb.) and 1 small onion, cut into 4 slices. Grill 5 minutes; turn over. Add 4 pineapple slices; continue grilling until chicken is cooked through, turning pineapple slices over after 3 minutes.
SQUEEZE 1 Tbsp. Miracle Whip Hot'n Spicy Dressing onto cut sides of each of 4 split kaiser rolls. Cover bottom halves of rolls with chicken, onions and pineapple.
COVER each with 1 Kraft Deli Deluxe Swiss Cheese Slice and top of roll.