Preheat the oven to 350°F.

Lightly spray a 9x13-inch baking dish with baking spray.

Remove the maraschino cherries from the jar and reserve the juice for the frosting.

Remove the stems from 15 cherries.

Slice the cherries in half, then slice each half again.

Set the chopped cherries aside.

Keep the remaining stemmed cherries for garnish.

In a large mixing bowl, combine the dry Devil’s food cake mix and Cherry Dr Pepper.

Using a stand mixer or handheld mixer, mix on low speed until just combined.

Using a large spoon, gently fold in the chopped cherries.

Pour the batter into the prepared baking dish.

Spread the batter evenly in the pan.

Bake for approximately 28 minutes, or until a toothpick or knife inserted into the center comes out clean.

Remove the cake from the oven.

Allow the cake to cool completely before frosting.

To prepare the frosting, add the softened butter and reserved maraschino cherry juice to a large mixing bowl.

Beat on medium speed until combined.

Reduce the mixer speed to low.

Add the powdered sugar 1/2 c at a time, mixing well after each addition.

Continue mixing until the frosting reaches a firm, spreadable consistency similar to canned frosting.

If the frosting is too thin, add up to 1/2 c additional powdered sugar, a little at a time.

Spread the frosting evenly over the cooled cake.

Gently score the frosting to mark the serving pieces.

Place one reserved stemmed cherry in the center of each marked piece.

If there are not enough stemmed cherries for every serving, remove the stems from the remaining cherries, slice them in half, and use them as garnish.

Place the cake in the refrigerator for 30 minutes to 1 hour to allow the frosting to set.

Sprinkle the chocolate shavings evenly over the top of the frosting.

Slice and serve.