STIR boiling water into dry gelatin mix in medium bowl at least 2 min. until completely dissolved. Drain pineapple and save juice. ADD enough ice to water and juice to measure 1-1/4 cups. Stir into gelatin until slightly thickened. Remove any unmelted ice. Gently stir in carrots and pineapple. Pour into large bowl. REFRIGERATE 2 hours or until firm. Serve with a dollop of mayo. Store leftover salad in refrigerator.