Grilled Flounder

2 pounds flounder or sole fillets
2 tablespoons lemon juice
1/2 cup grated Parmesan cheese
1/4 cup butter or margarine, melted

3 tablespoons mayonnaise
3 tablespoons chopped green onions
1/4 teaspoon salt
Directions:
1. Coat a piece of heavy-duty foil (about 14 in. x 14 in.) with nonstick cooking spray. Place fillets on foil; brush with lemon juice. Crimp foil, forming edges. Place foil flat on the grill (do not seal). Grill, covered, over medium-hot heat for 4 minutes. Combine Parmesan cheese, butter, mayonnaise, onions and salt; brush over fillets. Grill 3-4 minutes longer or until fish flakes easily with a fork.