Preheat an oven to 350 degrees F (175 degrees C). Grease a 9x13 inch baking dish.
Combine the cake mix and cola in a large bowl. Use a hand whisk to mix ingredients until light and smooth, about 3 minutes. Pour batter into prepared baking dish.
Bake cake in preheated oven until a toothpick inserted in the center of the cake comes out clean, 35 to 40 minutes. Allow cake to cool before cutting.
