HEAT greased grill to medium heat.
POUR 1/2 cup dressing over chicken in shallow dish; turn to evenly coat both sides of each breast. Refrigerate 15 min. to marinate.
REMOVE chicken from marinade; discard marinade. Grill chicken 6 to 8 min. on each side or until done (165ºF). Meanwhile, cover 4 plates with spinach.
SLICE chicken; place over salads. Top with fruit, onions and remaining dressing.