CHOCOLATE SANDWICH COOKIES
Source: Mom's Big Book of Baking: 200 Simple, Foolproof Recipes for Delicious Family Treats to Get You Through Every Birthday Party, Class Picnic, Potluck, Bake Sale, Holiday, and No-School Day by Lauren Chattman
Makes about 36 cookies

These are so much better than store-bought cookies that I just scream in frustration when my brand-conscious five-year-old insists that she prefers Oreos. Letting her lick the icing bowl goes a little way toward persuading her to at least try my version. And she never actually refuses to eat the finished product. I prefer butter in the filling for its flavor, but if you use butter you’ll have eat the cookies right away. Filling made with vegetable shortening will last several days.

FOR THE COOKIES:
1 cup unbleached all-purpose flour
6 tablespoons unsweetened Dutch-process cocoa powder, sifted
1/2 teaspoon baking soda
1/2 teaspoon salt
10 tablespoons (1 1/4 sticks) unsalted butter, softened
1 cup granulated sugar
1 large egg
1 teaspoon pure vanilla extract
FOR THE FILLING:
1/2 cup (I stick) unsalted butter, softened, or vegetable shortening
2 1/2 cups confectioners’ sugar
1 teaspoon pure vanilla extract
Pinch of salt
1 1/2 teaspoons water

MAKE THE COOKIES:
Combine the flour, cocoa powder, baking soda, and salt in a medium mixing bowl.

Cream the butter and granulated sugar together in a large mixing bowl with an electric mixer on medium speed until fluffy, 2 to 3 minutes. Add the egg and vanilla and beat until smooth. Stir in the flour mixture until just combined.

Divide the dough into 2 portions. Shape each portion into a log about 9-inches long and 1 /2-inches in diameter Wrap in plastic and refrigerate for at least 2 hours or for up to 24 hours. Dough logs may be wrapped in plastic and frozen for up to 1 month. Defrost the dough on the counter for 15 minutes before proceeding.

Preheat the oven to 350 degrees F.

Slice the dough into 1/4-inch-thick rounds and place the cookies on an ungreased baking sheet, leaving about 2 inches between each cookie.

Bake the cookies until they are dry on top, 6 to 8 minutes (a minute or two longer for partially frozen dough). Let them stand on the baking sheet for 5 minutes and then remove them from the sheet with a metal spatula to a wire rack and let them cool completely.

MAKE THE FILLING:
Cream the butter or vegetable shortening and confectioners’ sugar together in a large mixing bowl with an electric mixer on low speed until combined. Stir in the vanilla and salt. Add the water and beat on high until light and fluffy, about 5 minutes. Use the filling immediately, or cover the surface of the filling with plastic wrap. If using butter, store the filling in the refrigerator for up to 1 day and re-whip it before using. If using vegetable shortening, store the filling at room temperature for up to several days and re-whip it before using.

FILL THE COOKIES:
Spoon 1 teaspoon of the filling onto the flat side of a cooled cookie. Sandwich with another cookie, Repeat with the remaining cookies.

Chocolate Sandwich Cookies are best eaten on the day they are made. Store in an airtight container at room temperature.