1 1/4 cups all-purpose flour
1/3 cup unsweetened cocoa powder
1/2 tsp baking soda
1 stick plus 3 Tbl cold unsalted butter, cut into chunks
2/3 cup packed light brown sugar
1/4 cup sugar
1/2 tsp Fleur de Sel or Sel Gris
1 tsp Pure Vanilla Extract
1 tsp Chocolate Extract
5 ounces semi-sweet chocolate chips
Sift the flour, cocoa and baking soda together. Working with a food processor, process the butter and both sugars together until creamy and homogeneous. Add in the salt and extracts and give it a few pulses. Add in all the dry ingredients and pulse until the dough forms big, moist curds. Toss in the chocolate pieces and pulse just a few times to incorporate.
Important note: this is an unpredictable dough: sometimes it’s crumbly and sometimes it comes together and cleans the sides of the bowl. Happily, no matter what, the cookies are always great.
Turn the dough out onto a work surface and gather it together, kneading it if necessary to bring it together. Divide the dough in half. Shape the dough into logs that are 1.5 inches in diameter. Don’t worry about the length — get the diameter right, and the length will follow. Wrap the logs in plastic wrap and freeze them for at least 2 hours or refrigerate them for at least 3 hours.
When you’re ready to bake: Center a rack in the oven and preheat it to 325 degrees F. Line two baking sheets with parchment paper.
Working with one log at a time and using a long, sharp knife, slice the dough into 1/2-inch-thick rounds. (The rounds might crack as you’re cutting them — don’t be concerned, just squeeze the bits back onto each cookie.) Arrange the rounds on the baking sheets, leaving about 2 inches between them.
Bake the cookies for 12 minutes — don’t open the oven, just let them bake. When the timer rings, they won’t look done, nor will they be firm, and that’s just the way they should be. Transfer the baking sheet to a cooling rack and let the cookies rest until they are only just warm, at which point you can munch them, or let them reach room temperature (I think the texture’s more interesting at room temperature).