STIR boiling water into dry gelatin mix in medium bowl at least 2 min. until gelatin is completely dissolved. Stir in lemonade concentrate. Refrigerate 30 min. or until slightly thickened (consistency of unbeaten egg whites).
ADD half of the whipped topping; stir with wire whisk until well blended. Refrigerate 5 min. or until thickened. Gently stir in berries. Spoon into 16 paper-lined 2-1/2-inch muffin cups.
FREEZE 4 hours or until firm. To serve, remove and discard paper liners. Top desserts with remaining whipped topping. Store leftovers in freezer.