Salted Cocoa-Hazelnut Cookies

Instructions

1. Step 1

   In a large bowl, whisk together flour, cocoa powder, baking powder and salt.

2. Step 2

   In another bowl, using an electric mixer, beat together butter and sugar on medium-high until the mixture is superlight, fluffy and pale, about 2 to 3 minutes. Scrape down the sides of the bowl, and add in the eggs, 1 at a time, and vanilla extract, and beat until everything is well combined, about 2 minutes.

3. Step 3

   Add dry ingredients all at once, and mix on low until almost incorporated. Add hazelnuts, and continue to mix until just fully incorporated.

4. Step 4

   Scrape dough out of mixer, and divide it into 2 pieces onto cling wrap. Wrap each piece in cling wrap and roll them into logs about 1 1/2 to 2 inches in diameter, and 12 inches long.

5. Step 5

   Refrigerate the logs at least 2 hours, or up to 5 days.

6. Step 6

   Heat oven to 325 degrees.

7. Step 7

   Brush the outside of each log of dough with egg wash. Sprinkle sanding sugar (Demerara or regular granulated sugar also work here) onto a piece of parchment paper, and roll the logs in it. Slice log crosswise into 1/4-inch-thick slices.

8. Step 8

   Place dough slices on parchment-lined baking sheets 1 inch apart, and sprinkle with flaky salt. Bake until the edges are just set and cookies are baked through (difficult to tell with chocolate cookies, but the center should feel set when pressed gently), 12 to 15 minutes.