Preheat the oven to 375 degrees F.
Core apples. Place them in a casserole dish. Pour the entire can of soda over the apples.
Sprinkle sugar and cinnamon over the apples. Place the dish in the oven and bake for 45 minutes or until the apples are tender.
Top with whipped topping. Sprinkle with additional cinnamon, if you like. Enjoy!