In a large resealable plastic bag, combine the flour, Parmesan cheese and paprika. Cut each potato into eight wedges; dip in milk. Place in the bag, a few at a time, and shake to coat.
Place in a greased 15-by-10-by-1-inch baking pan. Drizzle with 2 tablespoons butter. Bake, uncovered, at 400 degrees for 20 minutes. Turn wedges; drizzle with remaining butter. Bake 20–25 minutes longer or until potatoes are tender and golden brown.
In a large bowl, combine dip ingredients. Serve with warm potato wedges.