The original recipe for these cookies was given to me by my friend, Pierre Hermé, the wonderful Parisian pastry chef. In the cookies’ first incarnation, they were called Sablés Chocolats, or chocolate shortbread. In their second, the one in which chopped chocolate was added to the sweet/salty dough, they were dubbed Sables Korova and were served at the Paris restaurant of the same name. Finally, a neighbor of mine gave them the name they truly deserve: World Peace Cookies. He was convinced that if everyone in the world could have these cookies, there would be planetary peace. I hope he’s right. What I know for sure is that everyone who has these cookies smiles and smiles are pretty powerful.
Sift the flour, cocoa and baking soda together and keep close at hand.
Working in the bowl of a mixer fitted with the paddle attachment or in a large bowl with a handheld mixer, beat the butter on medium speed until it is soft and creamy. (If you’d like, you can make the dough by hand using a rubber spatula or wooden spoon.) Add both sugars, the salt and the vanilla extract and beat for 2 minutes more.
Reduce the mixer speed to low and add the sifted dry ingredients, mixing only until they are incorporated – the dough may look crumbly, but that’s fine. For the best texture, you want to work the dough as little as possible once the flour is added. Toss in the chocolate pieces and mix only to incorporate.
Turn the dough out onto a smooth work surface, divide it in half, gather it together and, working with one half at a time, shape the dough into a log that is 1 1/2 inches in diameter. Wrap the logs in plastic wrap and chill for at least 3 hours or for up to 3 days.
Getting ready to bake: Center a rack in the oven and preheat the oven to 325 degrees F. Have two lined baking sheets at hand.
Working with a sharp thin-bladed knife, slice rounds that are 1/2 – inch thick. (The rounds often crack as you’re cutting them – don’t be concerned, just squeeze the bits back onto the cookie.) Arrange the rounds on the baking sheets leaving about 1 inch of spread space between each round and slide one of the sheets into the oven. Bake the cookies for 12 minutes – they won’t look done nor will they be firm, but 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 serve them or let them reach room temperature.
Repeat with the second sheet of cookies.
Storing: The dough can be made ahead and either chilled or frozen. In fact, if you’ve frozen the dough, you needn’t defrost it before baking – let it warm just enough so that you can slice the rounds; bake the cookies 1 minute longer. Packed airtight, baked cookies will keep at room temperature for up to 3 days; they can be frozen for up to 2 months.