01 -
Preheat the oven to 200°F and line a baking sheet with parchment paper.
02 -
In a large bowl, beat egg whites on low speed. Add cream of tartar, then gradually add sugar while increasing speed to high until stiff peaks form.
03 -
Pipe meringue onto prepared baking sheet, forming ghost-shaped mounds. Bake for 2 hours, then turn off the oven and leave meringues inside for 30 minutes to dry.
04 -
While meringues bake, combine softened butter, confectioners' sugar, milk, and purple gel food coloring. Mix until smooth and evenly colored.
05 -
Frost cooled cupcakes with the purple buttercream. Top each cupcake with a meringue ghost.
06 -
Use black decorating frosting to add eyes and mouth to each meringue ghost for a spooky effect.