Bake the Cupcakes: Start by baking the cupcakes according to your favorite recipe or boxed mix instructions. Allow them to cool completely before moving to the next step.
Prepare the Frosting: To create the ombre effect, divide the frosting equally into two bowls. Add red food coloring to one bowl and orange food coloring to the other, mixing each until you have the desired color intensity. Spread each color on a large piece of plastic wrap and roll that up as a log. Add the log to a piping bag fitted with a star tip.
Frost the Cupcakes: Pipe in a tall swirl so the frostring resembles a campfire-like shape. You'll see an exciting blend of red and orange hues in your frosting that resembles dancing flames.
Build Your "Campfire": Arrange 6 pretzel sticks on top of the cupcakes, pushing them gently into the frosting. They should resemble firewood or kindling stacked for a campfire. Thread 2-3 mini marshmallows on a toothpick and stick on the cupcake for a "S'mores" effect. If you are at ease using a culinary torch you can slighty torch the marshmallows.