Bergers-Style Cookies

FOR THE COOKIES: Adjust oven rack to middle position and heat oven to 350 degrees. Line 2 baking sheets with parchment paper. Whisk flour, baking powder, and salt together in bowl; set aside. Using stand mixer fitted with paddle, beat butter and sugar on medium-high speed until pale and fluffy, about 3 minutes.

Add egg white, cream, and vanilla and beat until combined. Reduce speed to low and add flour mixture in 3 additions until incorporated, scraping down bowl as needed.

Working with 1 heaping tablespoon dough at a time, roll into balls and space 2 inches apart on prepared sheets, 12 per sheet. Using your moistened fingers, press dough balls to form disks about 1/4 inch thick and 2 inches in diameter. Bake, 1 sheet at a time, until cookies are just beginning to brown around edges, 8 to 10 minutes, rotating sheet halfway through baking. Let cookies cool completely on sheet.

FOR THE FROSTING: Once cookies have cooled, combine chocolate chips, cream, and salt in large bowl. Microwave chocolate mixture at 50 percent power, stirring occasionally, until melted and smooth, 1 to 3 minutes. Whisk cocoa, sugar, and vanilla into chocolate mixture until smooth. (Frosting should be texture of thick brownie batter and register about 95 degrees.)

Flip cookies on sheets. Spoon 2 tablespoons frosting over flat side of each cookie to form mound. Let cookies sit at room temperature until frosting is set, about 3 hours. Serve. (Cookies can be stored in airtight container at room temperature for up to 2 days.)