Preheat the oven to 180°C (160°C fan forced). Line 2 x 12 cupcake trays with brown cupcake cases.
Open the cake box, remove enclosed frosting sachet and reserve for another use. Make up the cake mix as directed on the cake mix box using the eggs, butter and milk, then stir in the chocolate chips. Bake and cool as directed on the cake mix box.
For the decoration, spoon 1 tub of the vanilla frosting into a bowl and colour with green food colouring (see Tip). Spoon the remaining frosting into a disposable piping bag and snip off the end (leaving a 1cm round hole). Pipe a circle of the uncoloured frosting around the outside edge of each cupcake, leaving the centre free.
Using a small palette knife spread the green frosting over the ice cream cones and dip the top of each cone into the sprinkles to give a red border around the top edge. Invert each cone onto a cupcake.
For ears, spray the cashew nuts with the pink glitter or roll in shimmer powder and arrange either side of the cones in the frosting. Add 2 eyeballs, pushing gently into the vanilla frosting, and spray or dust the top of each cone with gold edible glitter for the finishing touch. Eat immediately or keep in an airtight container for up to 2 days.