Recipe from Alton Brown
6 oz 54% bittersweet chocolate, coarsely chopped
2 oz unsweetened chocolate, coarsely chopped
1-3/4 oz (not cups!) all purpose flour
1/2 tsp baking powder
1/2 tsp kosher salt
4 Tbsp unsalted butter, at room temperature
6 oz light brown sugar
2 large eggs, at room temperature
1 tsp vanilla extract
3 oz 70% bittersweet chocolate, coarsely chopped
3 oz 40% milk chocolate, coarsely chopped
2 oz cocoa nibs
Place the 54% bittersweet chocolate and unsweetened chocolate in a medium glass mixing bowl and microwave on high for 2 30-second intervals, stirring after each interval. If still not smooth, heat for 10 additional seconds at a time and stir until smooth. Set aside to cool at 90 degrees F, approximately 15 minutes.
Whisk the flour, baking powder and salt together, transfer to a paper plate and set aside.
Put the butter and sugar in the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until combined and looks like wet sand, about 2 minutes.
Whisk the eggs and vanilla together in a small bowl. Turn the mixer on low speed and slowly add the egg mixture until fully incorporated. Pour in the melted chocolate and mix to combine. Stop and scrape down the sides of the bowl.
With the mixer on low speed, add the flour mixture and mix until integrated. Add the 70% bittersweet chocolate, 40% milk chocolate and the cocoa nibs and mix until well combined. Cover the bowl with plastic wrap and refrigerate for 45 minutes.
Preheat the oven to 350 degrees F.
Scoop the dough using a 1-1/4 inch diameter disher or ice cream scoop onto parchment-lined half-sheet pans, placing 2 inches apart, 12 cookies per pan. Bake for 8 to 9 minutes, rotating after 5 minutes. Do not over-bake; the cookies may look wet and doughy.
Cool the cookies on the pan for 2 minutes, then transfer on the parchment paper to a cooling rack to cool completely.
Recipe courtesy of Alton Brown, 2011.
I do not claim any credit for this recipe. Posting it here only for educational cooking purposes, and because it seems to have disappeared from the interwebs for some reason.