Preheat oven to 350ºF. Scrub apples and core, but do not peel. The cored opening in the apple should be about 3/4-inch in diameter. Place apples in an 8-inch square baking dish. In a small bowl combine brown sugar, walnuts, raisins and cinnamon; stuff the mixture into the center of the apples and dot with butter. Carefully pour water around apples. Bake 30-40 minutes or until the apples are tender, but still keep their shape; baste apples with the pan juices a few times while baking. These are delicious as leftovers, cold or reheated, so you may want to bake extras.