Ask Casey: Killer Chocolate Cookies

Chocolate-Mint Thumbprints

Prep time: 30 minutes
Total time: 2 hours, including chilling time
Makes about 3 dozen cookies

Ingredients:

For the cookies:
• 4 oz. chopped bittersweet or semisweet chocolate (I use Valrhona discs or Callebaut chunks but if pressed, you could chop up a good-quality chocolate bar or use chocolate chips)
• 1 1/2 cups unbleached all-purpose flour
• 1/2 cup cocoa powder
• 3/4 teaspoon kosher salt
• 2 sticks softened unsalted butter
• 1/3 cup granulated sugar
• 2 tablespoons brown sugar
• 2 large egg yolks
• 1/2 teaspoon vanilla extract
• 1/2 teaspoon peppermint extract
• 3/4 cup turbinado or demerara sugar, for rolling

For the ganache filling:
• 3 oz. chopped chocolate: bittersweet, semisweet, milk, or a combination thereof
• 3 tablespoons heavy cream
• 1/2 teaspoon peppermint extract

Method:

Melt the chocolate in a small saucepan over low heat or in the microwave until just about melted (stir the microwaved chocolate every 30 seconds; it will retain its shape until touched, so stirring is crucial to see where you are in the melting process). Whisk until smooth, then let cool while you whisk together the flour, cocoa and salt in a separate medium bowl.

Beat the butter and sugars with an electric hand mixer or stand mixer fitted with the paddle attachment for 3 minutes, until light and fluffy.

Beat in the egg yolks and vanilla, then beat in the melted chocolate. Slowly add the dry ingredients until just incorporated. The dough will be very soft.

Turn the dough out onto a sheet of plastic wrap, pat into a flat disc, seal it up, and refrigerate for an hour or until fully chilled.

Preheat the oven to 350˚ and line two cookie sheets with parchment paper.

Pour the turbinado sugar into a shallow bowl. Roll up tablespoonfuls of the dough into balls and dredge in the sugar, then move to the baking sheets. Using your thumb, smush the balls slightly so there’s an indentation in each (this is where you’ll put your choco-mint ganache filling), and bake for 10 minutes.

Check the cookies and make sure your indentations haven’t disappeared as the cookie bakes and puffs; you’ll probably have to re-smush them again. Bake for 5 more minutes. Remove from the oven and cool the cookies on the baking sheets for 5 minutes before carefully transferring to racks with a spatula.

Once the cookies are completely cooled, transfer them back to a baking sheet (cram them in; it’s ok if they touch but should not overlap). Heat the remaining 3 oz. of chopped chocolate and cream in a small saucepan over low heat, whisking constantly, until smooth.

Stir in the mint extract and fill each of the thumbprint indentations, licking any extra ganache out of the bowl—you’re allowed. Place the baking sheet in the fridge for a half hour to chill and set the filling, then serve to your appreciative audience.