Get your little boos together, set ‘em up with cookies, frosting in every horrific color you can find, and any kind of candy you've got on reserve. Give them a few of the icing tubes and let them go to it.
Start by spreading frosting on the cookies — that gives something for the candy to stick to. Let them pile candy on as high as they want, or maybe they’ll get creative and try to make creepy decorations. If I were in charge, I’d say you have to be in costume to decorate at my table — but this is your house, and you can do it any way you like. It’s a Halloween cookie and candy free-for-all.
These cookies stand up well to decorating, and can be made in advance and stored as a slice-and-bake log in the fridge or freezer. (Keep in mind they must be refrigerated a total of at least 2 1/2 hours). Roll the log in sparkly sugar before you refrigerate it if you’d like, although if kids are doing the decorating, you might not be able to see much of it. (And its okay if there are no kids involved — grown-up are allowed to have fun, too.)
Slice and Bake Cookies
2 sticks butter, at room temperature
1/2 cup granulated sugar
1/4 cup confectioners’ sugar
2 large egg yolks, at room temperature
1/4 teaspoon salt
1 teaspoon vanilla extract
2 cups all-purpose flour
1. Beat butter in a mixer at medium speed until it is smooth. Add the granulated and confectioners’ sugars and beat until the mixture is smooth and velvety (not fluffy), about 1 minute. Beat in the egg yolks and vanilla, and add the salt. Reduce the mixer speed to low and add the flour, beating only until it just disappears. (Do not overbeat). Gather the dough into a ball, divide it in half, and wrap each half in plastic. Refrigerate 30 minutes.
2. Lightly dust your board with flour and roll each of the balls of dough into a log that is about 1 1/2 inches in diameter. (If younger kids are decorating, make the cookies a little larger.) Refrigerate at least 2 and 1/2 hours, or up to 3 days. (Logs may also be frozen and kept on hand for cookie emergencies).
3. Preheat the oven to 350 degrees. Line 2 baking sheet pans with parchment paper. Cut the logs across into 1/3 to 1/2-inch slices. Place them on the baking sheet pans with at least 1/2 inch between them.
Bake the cookies until they are set but not brown, about 14 minutes. Allow to cool completely before decorating.