how long to bake flounder fillets
1 Brush 1 tablespoon lemon juice over fillets. 2  Mix Parmesan cheese, melted butter, mayonnaise, green onions, and 2 tablespoons lemon juice in a bowl; spoon over the fillets. 3  Bake flounder in preheated oven for 10 minutes. 4  Switch oven to broil; broil fillets until the tops are just browned, 3 to 5 minutes.