Hazelnut-Orange Biscotti with Dark Chocolate-Orange Glaze

I thoroughly enjoy making biscotti for friends so I'm always on the lookout for good recipes.  I had a request for hazelnut recently so I tried this new recipe I adapted from Martha Stewart.  My daughter was a huge help as she spent nearly 2 hours cracking hazelnuts for me!  (We made several batches).  'One of the benefits of kids being enthralled with a simple thing like an old fashioned nutcracker!  Since there's orange zest in the biscotti, I thought a drizzle of dark chocolate-orange glaze would add a nice touch. The delicate orange flavor really compliments the hazelnuts.  I'll definitely be making these again.  

1-1/2 cups shelled hazelnuts
2-1/2 cups all-purpose flour
1-1/4 cups sugar
1 teaspoon baking powder
1 tablespoon grated orange zest (or more)
pinch of salt
3 large eggs
2 large egg yolks
1 teaspoon pure vanilla extract

Preheat the oven to 350 degrees.  Spread the hazelnuts on a baking sheet and toast for about 10-15 minutes until they give off a nutty aroma.  Cool slightly; place in a kitchen towel and rub vigorously to remove most of the skins.  Coarsely chop and set aside.  Combine all the dry ingredients in the bowl of an electric mixer.  In a medium bowl, beat together the eggs, yolks, and vanilla.  Add to dry ingredients and mix together until a sticky dough is formed.  Work in chopped hazelnuts.  Place dough on a lightly floured cutting board and divide into two portions.  Gently roll into logs about 12 inches long, and transfer to a greased and floured baking sheet.  Bake until golden brown and firm to the touch in the center, 25-30 minutes.  Remove from oven and cool slightly until easy to handle. Reduce oven to 275 degrees.  Carefully place logs on a cutting board.  Using a serrated knife, cut each log diagonally into 12, 1/2-inch thick slices.  Return slices to cookie sheet cut side up.  Bake until lightly toasted and hard, 15-20 minutes.  Let cool completely.  You can keep biscotti in an air-tight container for several weeks.  These freeze well unglazed in gallon freezer bags.  Just remove and thaw slightly, then glaze.
Makes 2 dozen    

Dark Chocolate-Orange Glaze

4 ounces dark chocolate baking chips or squares
1/2 to 1 teaspoon pure orange extract (I love Penzeys)

Place chocolate in a double boiler over simmering (not boiling) water.  Stir constantly until melted.  Remove from heat and add orange extract.  Drizzle biscotti slices with the glaze using a fork or place in a pastry or ziploc bag and drizzle.  *  I actually don't have a double boiler.  It works just as well to melt the chocolate in a stainless steel bowl placed inside of a pan of simmering water.  Just make sure the bowl is high enough so it doesn't touch the water.