Servings: Makes 40 cookies
For the dough, combine the butter, brown sugar and vanilla in the bowl of an electric mixer. Beat with the paddle on medium speed until well mixed and slightly lightened, about 2 minutes. Beat in the egg yolks, one at a time, beating smooth after each addition.
Decrease the speed to low and beat in the flour, just until it is absorbed. Use a large rubber spatula to give a final mixing to the dough. Scrape it out onto a piece of plastic wrap and shape it into an 8-inch square. Cover the dough with plastic wrap and slide it onto a cookie sheet. Chill the dough until it's firm, about 1 hour, or leave it for a couple of days before continuing.
When you are ready to bake the cookies, set racks in the upper and lower thirds of the oven and preheat to 350°.
Place the egg whites and ground almonds in two separate shallow bowls. Use a fork to break up the egg whites and make them more liquid.
Remove the dough form the refrigerator and use a bench scraper or knife to cut into eight 1-inch strips. Cut each strip into 5 equal pieces. Roll all the pieces of dough into spheres between the palms of your hands. Use a fork to lift one and then lower it into the egg white. Using a fork again, lift it out of the egg white and drop it into the almonds and nudge it around until it is completely covered in nuts. As the cookies are coated, arrange them on the two cookie sheets or jelly roll pans lined with parchment or foil, keeping them 1 1/2 inches from all sides.
Use the handle of a wooden spoon or another cylindrical implement about 3/8-inch in diameter, or a fingertip, to press a cavity into the top of each cookie and halfway down the depth of it.
Bake the cookies until they are firm and the almonds are golden, 15 to 20 minutes.
While the cookies are baking, make the filling: Whisk the coffee and vanilla into the chocolate.
Slide the cookies on the papers onto racks to cool. After the cookies have cooled, spoon or pipe a dab of the filling into each one. Sprinkle lightly with cinnamon.
Storage: For advanced preparation, keep these unfilled and stored between sheets of waxed paper in a tin or plastic container with a tight-fitting lid. Fill them just before serving.
© 2008 The Modern Baker. Excerpted by permission of DK Publishing. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Published on November 02, 2009