1. In a large bowl, combine sweet potatoes, flour, baking powder, cinnamon, honey, egg, and egg whites and stir with a fork until mixed well.
2. Coat a large non-stick skillet with cooking spray and place over medium heat. Drop the batter by about 2 tablespoonfuls into hot pan to make several pancakes. Flatten slightly with a spatula until about 3 inches across. Cook the pancakes until golden on both sides. Transfer the pancakes to a warm large plate and keep warm. Repeat with the remaining batter, coating the skillet with cooking spray, as needed.
3. To make the topping:
In a large skillet, stir together brown sugar, walnuts, orange juice, and cinnamon. Add the apples and cook over medium-high heat, stirring, until the apples are tender and the brown sugar has melted to form a syrup. Serve with the pancakes.
Good baking apples include: MacIntosh or Cortland