Roll fondant to 5mm thick. Using a 2.5 to 3 inch round cutter, punch circles in fondant and place on a very flat sheet tray that has been lined with parchment. Leave out overnight to dry.
Line conventional size cupcake pan with brown paper liners. Mix cake according to manufacturer’s instructions then use a #16 blue scoop to deposit 1.5oz batter into each cavity. Bake at 350 ͦF until cupcakes spring back lightly when touched. Let cool completely.
Make two piping bags out of each buttercreme color. Fit one with a very large straight tip, and another with a very small straight tip. Using the small tips, pipe sugar skull designs on each of the dried fondant discs. Using the large tip, pipe a dollop of buttercreme on each cupcake, top with prepared fondant disc.
No dark Devil’s Food Cake Mix available in your area? No problem, just substitute Dawn Exceptional® Baker's Request™ Devil's Food Cake Mix (00495128).