1

Preheat oven to 350°F. Place hazelnuts on a baking sheet; bake until light brown, about 8 minutes. Let cool. Line 2 large baking sheets with foil and spray the foil with nonstick cooking spray. Adjust the oven racks to divide the oven into thirds.

2

In a food processor, combine 2 tablespoons of hazelnuts, flour, 2 tablespoons of chocolate chips, cocoa, espresso powder, baking soda and salt. Process until nuts are finely ground; transfer dry ingredients to a large bowl. In the same food processor (no need to clean), combine sugar, eggs, egg whites and vanilla until slighty thickened, about 2 minutes. Add dry ingredients. Stir in remaining hazelnuts and chocolate chips.

3

Spoon one-fourth of the batter (about 3/4 cup) into a long rope, about 14 inches long and 1 1/2 inches wide, on one side of the baking sheet; repeat with remaining batter, making 2 ropes on each baking sheet, with space in between. Bake, reversing baking sheets once, until firm, about 15 minutes. Reduce oven temperature to 300°F.

4

Place logs on a cutting board. Cut with a serrated knife on diagonal into 1/2 inch thick slices, making 80 biscotti. Place slices upright on baking sheets, 1 inch apart. Bake until cut side feels dry to the touch, 20-25 minutes. Cool completely on wire racks. Store in an airtight container.