The flavors of Caesar salad— Parmesan cheese, lemon juice, Worcestershire sauce, and garlic—make a perfect accent for mild flounder fillets.
8 skinless flounder fillets, 4 to 5 oz. each
Kosher salt and freshly ground black pepper
1/3 cup good-quality mayonnaise
1-1/2 oz. (1/2 cup) freshly grated Parmigiano Reggiano, grated on the small holes of a box grater
1-1/2 Tbs. loosely packed finely grated lemon zest (from 1 large lemon)
1 Tbs. fresh lemon juice
1/2 tsp. Worcestershire sauce
1 small clove garlic, minced
2 Tbs. coarsely chopped fresh flat-leaf parsley
Position a rack 4 inches from the heat element and heat the broiler on high. Lightly season both sides of the fillets with salt and pepper. Set a fillet before you, skinned side up, and starting at the narrow end, roll up the fillet. Repeat with the remaining fillets.
Spray a broiler pan with nonstick cooking spray. Arrange the flounder rolls, seam side down, in the pan. Broil until the tops are lightly browned, 7 to 8 min. Meanwhile, whisk the mayonnaise, Parmesan, lemon zest and juice, Worcestershire, and garlic in a small bowl. Season with pepper to taste.
When the tops of the fillets are lightly browned, remove the fish from the broiler. Spread equal amounts of the mayonnaise mixture over the top of each fillet. Return to the broiler until the topping is golden brown and bubbling, 1-1/2 to 2 min. Transfer the fillets to four dinner plates and sprinkle with the parsley. Serve immediately.