Start by preparing your cake mix as directed on the box.
Line your cupcake tin with liners, and fill each one HALF way.
Bake according to box instructions.
Let cool completely.
If you are using a pipping tool with your icing, start in the center and work your way out and up. Do not make it too high.
Place mini marshmallows on top of your icing.
Take your decorative straws and cut into 1/3's.
Push your straw down into the cupcake.
Serve and enjoy!