Black Chocolate Biscotti

Directions

1. 1
   Position racks to the upper and lower thirds of oven. Preheat the oven to 350°F.
2. 2
   Line two jelly roll pans with parchment paper and set aside.
3. 3
   In a medium saucepan, melt butter over low heat.
4. 4
   Remove from heat.
5. 5
   Add the dark chocolate and let mixture rest 1 minute.
6. 6
   Stir gently until the chocolate is melted and smooth; set aside.
7. 7
   Combine the flour, cocoa powder, baking powder, salt and baking soda in a medium bowl; whisk thoroughly; set aside.
8. 8
   Mix the Kahlua, dissolved espresso powder and vanilla in a small bowl; set aside.
9. 9
   In a large bowl beat eggs with electric mixture on medium speed for 2 minutes.
10. 10
    Add sugar, in 3 additions, mixing for 20 seconds after each addition.
11. 11
    Beat 1 minute longer.
12. 12
    Reduce speed to medium low.
13. 13
    Add Kahlua mixture and chocolate butter mixture; mix thoroughly scraping down the sides of the bowl as necessary.
14. 14
    On low speed, add dry ingredients, in 2 additions, mixing only to combine.
15. 15
    Using rubber spatula, fold in chopped chocolate and nuts.
16. 16
    Let batter stand for 10 minutes to thicken.
17. 17
    Portion the dough onto the jelly roll pans, forming 4 logs, each measuring 1 1/2 inches wide by 12 inches long, smoothing tops and sides with moistened hands.
18. 18
    Brush tops and sides with egg wash.
19. 19
    Bake for 20 to 22 minutes, or until tops are just set.
20. 20
    Remove from oven and let stand for 20 minutes.
21. 21
    Reduce oven temperature to 300°F Carefully place 1 log at a time on a cutting board. Using a thin, sharp serrated knife cut into generous 1/2 inch slices.
22. 22
    Lay slices on their sides and toast in oven for 12 minutes.
23. 23
    Turn the slices over carefully and toast for 8 minutes longer.
24. 24
    Allow cookies to cool on pans; the biscotti will become firm and crisp as they cool.
25. 25
    Store biscotti, layered between sheets of waxed paper in an airtight container at room temperature for up to 3 weeks.
26. 26
    If desired, biscotti may be frozen for up to 3 months.