• Preheat the oven to 350 degrees and prepare a 9x13 baking dish with non-stick cooking spray.

Make the cake

• In a large bowl, whisk together the all-purpose flour, white granulated sugar, baking soda, and salt until fully incorporated. Set aside.
• In a small saucepan, simmer the entire can of coca cola over medium heat until it reduces to about ½ cup. Use a measuring cup to accurately measure and discard the extra.
• Add the unsalted butter and baking cocoa and whisk until the butter is melted and the cocoa is completely dissolved. Remove from heat and cool for 5 minutes.
• Once cooled, add the Coca Cola mixture to the flour mixture. Add the eggs, buttermilk and vanilla and use an electric mixer on medium speed to blend until well combined.
• Pour the cake batter into the prepared cake pan. Bake for 30 minutes or until a toothpick or knife inserted in the center comes out clean.

Mke the frosting

• While the cake is baking, prepare the frosting.
• In a small saucepan over medium heat, reduce the second can of Coca Cola by simmering over medium heat until reduced to a ½ cup. Use a measuring cup to accurately measure and discard any extra.
• Add the butter, vanilla and cocoa to the mixture and whisk until butter is fully melted and mixture is smooth. Remove from heat.
• Add the powdered sugar ½ cup at a time, whisking together until dissolved. Repeat until all four cups are incorporated.

Finish the Cake

• Pour the frosting over the baked cake. Allow the cake to cool before serving.
• Optional: Serve with ice cream, whipped topping, chocolate syrup or cherries for an extra special presentation.