Preheat your oven to 350°F (175°C) and line a cupcake pan with cupcake liners.
In a standing mixer, combine the cake mix, butter, milk, and eggs. Mix on medium speed until well combined.
Scoop the batter into the cupcake liners, filling them about 3/4 full.
Bake for 21 minutes or until a toothpick inserted into the center comes out clean. Allow the cupcakes to cool completely.
In a mixing bowl, beat together the butter, powdered sugar, vanilla extract, and heavy cream until stiff peaks form.
Divide the frosting into two bowls. Add yellow gel food coloring to one bowl and orange gel food coloring to the other.
Mix the graham cracker crumbs and cocoa powder in a small bowl.
Assemble mini marshmallows on toothpicks by placing two marshmallows on each.
Frost each cupcake and dip them into the graham cracker mixture to create the ‘campfire’ base.
Pipe the colored frosting in the center of each cupcake to resemble flames.
Add pretzel rods around the ‘fire’ to mimic logs and place the marshmallow sticks on top to complete the campfire look.