In a large resealable plastic bag, combine the flour, salt and pepper. Add halibut, one piece at a time, and shake to coat. Place in a 13-in. x 9-in. baking dish coated with cooking spray.
In a small bowl, combine the sour cream, mayonnaise, pickle, onion, dill, lemon juice and seasoned salt; spread evenly over halibut. Sprinkle with Parmesan cheese. Bake, uncovered, at 350° for 25-30 minutes or until fish flakes easily with a fork.