Double Dark Chocolate Shortbread Cookies

[hiromisky]

Double Dark Chocolate Shortbread
(makes about 12-14 cookies, double the recipe if you want to) 
oven to 325
1 stick (1/2 cup) unsalted butter, softened
1/4 cup confectioner's sugar
1 teaspoon vanilla
3/4 cup all-purpose flour
1/4 cup dark cocoa powder
1/2 cup dark chocolate chips

• Put the flour, sugar, and cocoa powder in the bowl of a food processor and pulse to combine well.
• Drop in the butter and vanilla and pulse until the mixture just comes together. 
• Stir in the chocolate chips and turn the dough out onto a board and form into an 8" log. 
• Wrap it in waxed or parchment paper and twist both ends to secure.  Refrigerate for at least an hour, or overnight.  You can also freeze the dough for later use.
• Slice the log into 1/2" slices with a sharp knife.
• Put on a parchment lined baking sheet and bake in the center of the oven at 325 for 12 to 15 minutes.  They will feel slightly soft, don't over bake them.
• Cool for a few minutes on the pan and then transfer to a rack.
• If you're going to give them away make sure they are completely cool before you package them.

{source}