Preheat your oven to 350 degrees F. Line a muffin tin with cupcake liners and set it aside.
In a large mixing bowl, whisk together the cake mix and strawberry soda until smooth and combined.
Pour the cake batter into the lined muffin tin cups so that they are 1/2 way full.
Bake for 14-16 minutes or until a toothpick inserted in the center comes out clean. Remove from the oven and then transfer the cupcakes to a wire rack to cool completely.
Once the cupcakes are cooled, beat together the butter and cream cheese in a large mixing bowl. Add the powdered sugar 1 cup at a time. Once the sugar is all mixed in add the vanilla and mix until smooth.
Frost the cupcakes with an offset spatula or a piping bag with your preferred tip attached. (You can also use a ziploc bag with a corner cut off instead of a bag with a tip.)
Garnish each cupcake with half a strawberry or strawberry slice. Store in the fridge until ready to serve.