Triple-Chocolate Biscotti

Heat the oven to 325~. Toast the hazelnuts on a baking sheet for 10 to 15 minutes, until they emit a nutty aroma but haven't turned dark brown inside. If they still have skins, cover the nuts with a dishtowel or paper towels for a few minutes after you take them out of the oven, and then rub the nuts with the towel to remove the skins. Set aside to cool. Put the flour, cocoa powder, baking soda, salt, sugar, and ground coffee beans into the bowl of an electric mixer fitted with a paddle. Combine these ingredients on medium-low speed and then toss in the nuts and chocolate chips. In a separate bowl, lightly whisk together the eggs and vanilla extract. With the mixer running on low speed, slowly add the egg mixture to the mixing bowl and mix until the dough comes together. Remove the bowl from the mixer and mix in any remaining dry ingredients from the bottom by hand. Form the logs as described in the Almond Biscotti recipe, making four logs instead of three. Bake the logs at 325~ for 30 to 35 minutes until the sides are firm, the tops are cracked, and the dough inside the cracks no longer looks wet. Remove the baking sheet from the oven and reduce the temperature to 300~. Let the logs cool on the baking sheet for at least 10 minutes before slicing. Cut the logs on a slight diagonal into 3/4" thick slices. Place the biscotti flat on the baking sheet and dry them in the oven for about 25 minutes, until the biscotti offer resistance when pressed. Transfer the biscotti to a rack to cool. While the biscotti are cooling, chop the white chocolate and melt it in a microwave on low power or in a double boiler over simmering water. With a knife, spread white chocolate on one cut side to each cooled biscotti. Put the chocolate on one cut side of each cooled biscotti. Put the biscotti, white-chocolate side down, on a parchment-lined baking sheet. Allow the chocolate to harden. Peel the biscotti from the parchment and store in an airtight containe