To make the fondant Oogie Boogie Mickey ears, dust your surface and rolling pin with powdered sugar and roll out the bright green fondant to ¼" thick. Cut out 24 x 4" circles with a round cutter. Place onto a cookie sheet lined with parchment paper and leave to dry for at least 6 hours and up to 24 hours if possible. When fully dried, draw Oogie Boogie's face onto the ears with a black edible marker.
To make the bows, use about a tablespoon of purple fondant and press it into a large bow mold. Make 12 total. Carefully remove and place on a cookie sheet lined with parchment paper.
Make smaller bows with black fondant and pop out of the mold - make 12 total. Stick the black bows to the front of the purple bows by rubbing or brushing some water to the back of the smaller black bow and placing it in the middle of the purple bow. Leave to dry for a few hours - up to 24 if possible. When dried, draw on silver dots with an edible marker.
Make a few extra fondant decorations as backup, just in case any break!
Preheat oven to 180C/350F/Gas 4 degrees and line cupcake pan with cupcake liners.
Using an electric mixer, mix the cake mix with the milk, eggs, and softened butter until combined.
Use an ice cream scoop to evenly distribue the cake batter between the liners.
Bake for 20 minutes or until a toothpick inserted into the center of the cupcakes comes out clean.
Allow to cool in pan for 5 minutes before transferring to a wire rack to cool completely.
To make the frosting, use an electric mixer to combine the butter, powdered sugar, heavy whipping cream, and vanilla on medium speed until combined and smooth.
Scoop the frosting into a piping bag fitted with a large star tip.
Pipe frosting swirls onto the cooled cupcakes.
Place the bow in the middle of the frosting.
Place the Oogie Boogie Mickey ears on either side of the bow.