Line an 18x13-inch rimmed baking sheet with parchment or wax paper.
In a medium bowl, whisk together flour, baking powder, and salt; set aside.
In a large bowl set over a double boiler, melt 60% and 70% chocolate morsels. (Water should not be touching bottom of bowl.) Whisk in butter; remove bowl from heat, and let mixture cool to room temperature.
In the bowl of a stand mixer fitted with the whisk attachment, beat eggs and granulated sugar at high speed until very thick and pale in color, 6 to 8 minutes. Slowly pour in cooled chocolate mixture, scraping down sides of bowl to ensure even mixing. Reduce mixer speed to low, and beat in dry ingredients until combined, stopping occasionally to scrape down sides of bowl. Beat in espresso and vanilla. Change from whisk to paddle attachment, and beat in frozen chocolate morsels until incorporated.
Pour mixture into prepared pan. Place a sheet of parchment or wax paper over surface of dough, covering completely. Refrigerate overnight.
Preheat oven to 350°. Line several rimmed baking sheets with parchment paper.
In a large bowl, place confectioners’ sugar. Using a 1-tablespoon levered scoop, scoop dough and drop into confectioners’ sugar, several at a time, tossing to coat. Place 2 inches apart on prepared pans. Bake until puffy and cracked, 13 to 15 minutes. Remove from pans, and let cool completely on wire racks. Store in an airtight container at room temperature with layers separated by wax or parchment paper.
Notes
This recipe yields a large amount of cookies that can be stored in the freezer for up to a month. Store in an airtight container with layers separated by wax or parchment paper.
Adapted from Lisa White from Willa Jean.
Recipe by Bake from Scratch at https://staging.bakefromscratch.com/chocolate-espresso-cookies/