Topping:
Preheat oven to 375 degrees; spray a large cookie sheet with nonstick cooking spray. In a medium bowl, combine the flour, brown sugar, baking powder, cinnamon, nutmeg, ginger and salt; mix well. Using a pastry blender or fork, cut in the margarine until the mixture resembles coarse crumbs. Stir in the apples. In a small bowl, combine the applesauce, buttermilk and egg; mix well. Add to hte dry ingredients; stir just until moistened. The dough will be sticky. Place the dough on the cookie sheet. With wet fingers, shape it into an 8-inch circle about 3/4-inch thick. In a small bowl, combine sugar and cinnamon; sprinkle over the top of the dough. With a sharp knife, score the top surface into 8 wedges, cutting about 1/4-inch deep. Bake for 18 to 22 minutes, or until golden brown and a toothpick inserted in the center comes out clean. Cut into wedges. Serve warm.