Set your oven to preheat at 350°F (175°C).
In a sizable bowl, empty the dry angel food cake mix and fold in the cherry pie filling along with the vanilla extract. Stir with care until the mixture becomes uniformly thick and airy.
Transfer the prepared batter into a 9x13-inch (23x33 cm) baking dish—do not grease the pan. Use a spatula to level the surface evenly.
Bake the cake in the center rack of your oven for 35 to 40 minutes, or until the top develops a golden crust and springs back gently to the touch.
Remove the pan from the oven and allow the cake to cool fully in the baking dish, resting it on a wire rack.
Once cooled, spread the whipped topping evenly across the surface. If desired, finish with a flourish of fresh cherries or shavings of white chocolate. Slice into bars and serve.