Preheat oven to 350 degrees.
In a mixing bowl, stir together flour, cocoa, sugar and baking powder. In a separate bowl whisk together the eggs, yolks and almond extract. Add wet mix to dry and stir until the dough comes together, about 2 minutes. Add hazelnuts and chocolate chips and mix until just incorporated. Roll the dough into 3 logs each about 10 by 2 inches. Place a piece of parchment onto a baking sheet and place logs on sheet. Place in oven and bake 20 minutes until light golden brown and remove. Allow to cool 5 minutes and cut logs on a slight diagonal into pieces 1/2-inch thick. Lower heat to 300. Return cut biscotti to baking sheet, just a little bit apart from each other, and place in oven. Bake 20 minutes until crisp and dry. Cool and serve.
Recipe Courtesy of Mario Batali