Heat oven to 325°F. Coat a 13 x 9 x 2-inch baking dish with butter-flavored cooking spray.
Sprinkle fish on both sides with the mesquite seasoning, salt and black pepper. Place into the prepared baking dish. Pour evaporated milk over fish; dot with butter.
Bake at 325°F for 20 to 23 minutes or until fish flakes easily. Garnish with parsley; serve immediately.
