Place fish in a large shallow container; pour milk over fish. Cover and refrigerate overnight.
Drain fish. Place fish in a small Dutch oven with water to cover; bring to a boil. Boil 5 minutes or until fish is tender.
Place fish on rack in a shallow roasting pan. Rub with lemon juice and butter; sprinkle with pepper. Broil fish 6 inches from heating element 5 minutes or until fish flakes easily when tested with a fork.
Transfer fish to a warm serving platter, and sprinkle with parsley. Serve immediately.