Dark Chocolate Shortbread Sandwich Cookies

Prep Time 1 40

Cook Time 15

Filling Cookies 5

Total Time 2

Servings 28 sandwich cookies

Large and small digital scale (or liquid measuring cup, dry measuring cups, and measuring spoons)
Stand mixer with paddle attachment (OR hand mixer with a large bowl)
Silicone spatula
Medium bowl and large bowl
Plastic wrap
Whisk
2 Baking sheets
Parchment paper
Rolling pin with ¼” guides
Wire cooling rack
Piping bag
Scissors
#12 Wilton Piping tip (optional)
Coupler (optional)

2 cups (250g) all-purpose flour
1 cup (87g) unsweetened alkalized cocoa powder (I used black cocoa powder - see "Notes" section)
½ tsp (2g) baking soda
2 sticks (226g) unsalted butter, softened
¾ tsp (3g) salt
¾ cup (161g) granulated sugar

In a medium bowl, sift flour, cocoa powder, and baking soda. Whisk to combine and set aside.
Place the butter In the bowl of the stand mixer and beat with the paddle attachment on medium low speed for 30 seconds until the butter is smooth.
Add the salt and sugar and cream for 2 minutes on medium speed until light and fluffy.
Add the dry ingredients in 3 additions, mixing on the lowest speed until just combined. After the last addition, mix for a few more seconds until the dough comes together.
Tip the dough onto a sheet of plastic wrap and use the plastic wrap to knead the dough into a square. Wrap the dough in plastic wrap and refrigerate for at least 1 hour (or until firm).
You can make the cookie dough up to 2 days ahead of baking and keep it in the fridge.

While the dough is chilling, make the White Chocolate American Buttercream Filling.
Place butter in your stand mixer fitted with the paddle attachment or in a large bowl if using a hand mixer. Beat the butter at medium speed for 1 minute until the butter is soft and creamy. Add the sifted powdered sugar, heavy cream, vanilla, and salt. Mix on the lowest mixer setting until the powdered sugar is moistened. It’s ok if there are a few lumps at this point.
Increase the speed to medium and beat for 2-3 minutes. This will smooth out any lumps in the buttercream and incorporate air. During this process, the buttercream’s color will lighten, and the volume will increase. Beat the buttercream until it reaches stiff peaks (i.e., the buttercream will stand straight up when you pull out the beater and hold it upright).
Add the melted and cooled white chocolate and stir to combine.
Cover the bowl with plastic wrap and set to the side at room temperature until ready to use.

Approximately 30 minutes before baking the cookies, preheat the oven to 325°F/170°C, and line two baking sheets with parchment paper.
Unwrap the dough and place it between two sheets of parchment paper (or the plastic wrap you used to chill it and a sheet of parchment paper). Use a rolling pin to roll the dough to ¼ inch thickness. Cut desired cookie shapes using a cookie cutter (I used a 2” fluted circle cutter) and transfer the cookies to the prepared baking sheet.
If the dough softens while rolling and cutting, place the dough back in the fridge for a few minutes. Place the sheet of parchment paper onto a baking sheet and put the whole pan in the fridge so the cookies chill flat. This will make it easier to cut the cookies so they keep their shape, and this will also keep the cookies from spreading when baking.

Bake for 13-15 minutes until you can smell the black cocoa powder. It will be difficult to tell when the cookies are done by sight because they are black. You can bake a couple test cookies and allow them to cool before tasting to determine if they are the texture you want. The cookies should be crispy.
Remove the cookies from the oven and allow the cookies to cool on the baking sheet for 5 minutes before moving the cookies to a wire rack to cool completely.

Use a spatula to fill a piping bag with filling and cut off the tip of the bag. You could use a #12 or #32 Wilton piping tip if you’d like for piping the filling.
Flip half the cookies over and pipe a circle of filling in the middle of the cookie leaving a small ring of cookie unfilled around the edge. Place a second cookie on top of the filling and push gently to sandwich the cookies.
The cookies are best (and crisp) the day they are baked. They will soften as they sit (especially when filled). You can store the unfilled cookies in an airtight container at room temperature for up to 3 days. Filled cookies should be stored in the fridge up to 7 days.

I used Guittard Cocoa Noir. This makes a very dark dough, just like Oreos.
This recipe was adapted from the “TKO” recipe in Bouchon Bakery by Thomas Keller and Sebastien Rouxel.