Put the soft butter in the bowl of a stand mixer fitted with the paddle attachment. If you don't have a stand mixer, use electric beaters, or a wooden spoon and elbow grease :)
Sift the cocoa powder and the confectioner's sugar into the bowl, and cream with the butter. Start the machine on low or you will have a mess on your hands. Mix until everything is very smooth, no lumps.
Beat in the espresso powder and the vanilla paste.
Add the flour and mix until all the flour is incorporated, but don't overwork the dough. Fold in the chocolate chips.
Turn the dough out onto a piece of plastic wrap, and form into a round flat disk, as if you were making pie dough. Wrap it up and refrigerate until firm enough to roll out, about an hour and a half.
Roll the dough out between two large sheets of plastic wrap so you don't have to deal with it sticking. Roll to a thickness of about 1/3 inch. Cut out the cookies with a 2" cutter. Reform the dough as necessary. (If the dough is too firm to work with straight from the fridge, let it sit to soften for a while.)
Put the dough on a parchment lined baking sheet and bake for about 12 minutes, The cookies may appear underdone, but they will firm up as they cool. Don't over bake.
Let the cookies cool for several minutes on the tray, then carefully move them to a cooling rack.
Dust with powdered sugar, if desired, after the cookies have cooled.
These cookies are fine cooking at anywhere between 325F and 350F, so I split the difference at 335F. In any event they will be done between 12 and 15 minutes. Don't over bake.
https://theviewfromgreatisland.com/deepest-chocolate-espresso-chip-cookies/ November 9, 2013