Preheat oven to 350. Sift together flour, cocoa, and espresso powder; set aside.
Using an electric mixer, combine butter, powdered sugar and vanilla until creamy. Gradually beat the flour mixture into the butter mixture, scraping down sides of bowl twice.
Using smallest cookie scoop, place cookie dough on ungreased baking sheet. Using a dinner fork, press tines into dough to flatten slightly. Bake just until firm to the touch, about 12 minutes.