In a greased 1-½ qt baking dish, layer half of the sweet potatoes and apples. Combine brown sugar, nutmeg, allspice, salt, and pepper; sprinkle half of this mixture over the apples. Dot with half the butter. Repeat layers. If you're dish is shallow and wide instead of deep, you'll only be able to do one attractive layer.
Cover and bake at 350*F for 30 minutes. Baste with pan juices. Bake, uncovered, 30 minutes longer or until the apples are tender.