Chocolate Peppermint Bark Cookies

From Bon Appetit.
Ingredients
- 2 cups all purpose flour
- 1/4 teaspoon salt
- 1 cup (2 sticks) unsalted butter, room temperature
- 1 cup sugar
- 1 teaspoon vanilla extract
- 1 large egg yolk
- 6 ounces bittersweet or semisweet chocolate, chopped
- 1/2 cup finely chopped red-and-white-striped hard peppermint candies or candy canes (about 3 ounces)
- 2 ounces high-quality white chocolate (such as Lindt or Perugina)
Instructions
- Preheat oven to 350°F. Spray 13x9x2-inch metal baking pan with nonstick spray. Line bottom of pan with long strip of 9-inch-wide parchment paper, leaving overhang on both short sides of pan.
- Whisk flour and salt in medium bowl.
- Using electric mixer, beat butter in large bowl until creamy, about 2 minutes.
- Gradually beat in sugar. Continue beating until mixture is light and fluffy, stopping occasionally to scrape down sides of bowl, about 3 minutes.
- Beat in vanilla, then egg yolk.
- Gradually add flour mixture, beating on low speed just to blend.
- Drop dough by tablespoonfuls onto prepared baking pan, spacing evenly. Using moistened fingertips, press dough to form even layer over bottom of pan. Pierce dough all over with fork.
- Bake cookie base until light golden brown and slightly puffed and edges begin to come away from sides of pan, about 30 minutes.
- Place pan on rack; immediately sprinkle bittersweet chocolate over. Let stand until chocolate softens, about 3 minutes.
- Using small offset spatula, spread bittersweet chocolate over top of cookie in thin even layer. Immediately sprinkle chopped peppermint candies over.
- Stir white chocolate in medium metal bowl set over saucepan of simmering water until melted and smooth. Remove from over water. Using fork, drizzle white chocolate all over cookies.
- Chill until white chocolate is set, about 30 minutes.
- Using paper overhang as aid, lift cookie from pan and transfer to work surface. Using large knife, cut cookie into irregular pieces.