Green Goddess Dressing: In medium-size bowl, whisk together mayonnaise, sour cream, vinegar, lemon juice, salt and pepper. Stir in parsley, scallions and chives. Cover and refrigerate until ready to use.

Swordfish and Potato Salad: Place potatoes in medium-size saucepan; cover with cold water. Bring to a boil over high heat. Reduce heat to medium-high; simmer until fork-tender, about 8 minutes. Drain potatoes. Place in medium-size bowl; let cool slightly. Reserve 1/2 cup of dressing to serve with fish. Add remaining dressing to potatoes; gently stir to coat potatoes. Cover and refrigerate for at least 1 hour.

Prepare outdoor grill with hot coals or heat gas grill. Lightly brush grill grid with vegetable oil. (Or cook using oven method, below.)

Sprinkle 1/2 teaspoon lemon pepper on each side of swordfish. Grill 4 minutes on one side. Turn over; grill 3 minutes or until cooked through. Serve swordfish with potato salad and reserved dressing on the side.

Oven Method: Heat broiler. Coat broiler-pan rack with nonstick cooking spray. Place seasoned swordfish steaks on rack in broiler pan. Broil 4 to 6 inches from heat 4 minutes on one side. Turn; broil for another 3 minutes.