- 1/4 cup reduced-fat mayonnaise
 - 1 tablespoon cider vinegar
 - 1 tablespoon prepared mustard
 - 1 tablespoon honey
 - 1/8 teaspoon cayenne pepper
 - 4 large onions, cut in 1/2 inch slices
 - 6 (6 ounce) fillets trout
 
- Coat grill rack with nonstick cooking spray before starting the grill. In a bowl, combine the first five ingredients. Place onions cut side down on grill rack with sides touching. Arrange fillets on onion slices. Cover and grill over medium-hot heat for 5 minutes. Baste with mustard mixture. Cook 5-6 minutes longer or until fish flakes easily with a fork, basting frequently. Discard onion slices.