Preheat your oven to 200 degrees F and line a baking sheet with parchment paper.

Pour egg whites into a large bowl and begin beating them on low speed with an electric mixer.

Once you see some bubbles forming in your egg whites, add the cream of tartar.

Slowly sprinkle in the sugar while gradually increasing your mixer speed to its highest setting.

Continue mixing until your mixture turns bright white and forms semi-stiff peaks.

Scoop the meringue mixture into a piping bag fitted with Wilton tip #12.

On your lined baking sheet, pipe out mounds of meringue.

Bake in your preheated oven for 2 hours. After baking time is complete, turn off the heat but leave them inside for an additional 30 minutes.

While your meringues cool down, prepare your buttercream frosting by combining softened butter, confectioners’ sugar, and milk in a large bowl.

Using an electric mixer, beat together all ingredients until well incorporated and smooth.

Add one small drop of violet gel food coloring and mix until you achieve a lovely purple hue.

Transfer the purple buttercream into another piping bag fitted with Wilton tip #12 and frost each cupcake generously.

Once baked meringues have cooled slightly, gently remove them from the baking sheet.

Attach Wilton tip #3 onto your black decorating frosting tube and pipe eyes and mouths onto each meringue cookie.

Place one cute meringue ghost atop each frosted cupcake.