How to Make It
Combine the mayonnaise, pickle, onion, lemon juice and tarragon. Season with salt and pepper.
Preheat the broiler. Arrange the fish fillets on a broiler pan and brush with the butter. Sprinkle with the dill, paprika, salt and pepper. Broil until the fish is golden and cooked through, about 4 minutes.
Spread the tartar sauce on the tops and bottoms of the roll, top with a lettuce leaf and tomato slice and serve.