Prepare cake batter according to the package directions for making cupcakes. Bake and let cool completely.
Crush Oreo cookies in a food processor until fine crumbs. Pour crumbs into a large shallow dish or cereal bowl.
Roll the frosted cupcakes in the Oreo crumbs, making sure to evenly coat the top of the frosting
Take a fresh mint leaf and place the stem into the center of the cupcakes so that it is standing upright.