Edible icing ghosts, such as these or these. You can also find edible icing ghosts at many craft stores.
1 stick butter, softened
2 cups powdered sugar
1 teaspoon vanilla extract
2–3 tablespoons heavy cream
Orange gel food coloring
Instructions
Preheat the oven to 350°F. Line cookie sheets with parchment paper and arrange the cookie dough on the prepared pans.
Gently press an edible icing ghost onto half of the cookies. Bake the cookies according to the package directions.
Allow the cookies to cool completely before assembling the sandwiches.
To make the frosting, beat the softened butter until smooth and creamy. Add the powdered sugar, vanilla, and 2 tablespoons of heavy cream. Beat until light and fluffy, adding another tablespoon of heavy cream if needed to reach your desired consistency.
Add orange gel food coloring and mix until the frosting reaches your desired shade of orange.
Flip one of the plain cookies upside down. Pipe a generous dollop of orange frosting onto the cookie, or spread it on with a knife.
Top with one of the ghost cookies and gently press the cookies together to create a sandwich. Repeat with the remaining cookies.