Categories: Desserts 
      Yield: 36 cookies 
  
      1 c  Hazelnuts (about 4 oz) 
    1/4 lb Butter, unsalted, room temp 
      1 c  Sugar 
      1 lg Lemon, grated zest of 
      2    Eggs 
      1 t  Vanilla extract 
      2 c  All purpose flour, 
           Plus 2 Tbsp 
      1 ts Baking powder 
    1/4 ts Salt 
  
  I just made this recipe once, and I substituted toasted sliced 
  almonds for the hazelnuts. It was really good. 
  Preheat oven to 350-F. Spread the hazelnuts on a baking sheet and 
  toast in the oven for 8 to 10 minutes, until fragrant. Place the nuts 
  in a dish towel and rub them together to remove some of the skin. 
  Coarsely chop the hazelnuts and set aside. 
  In a large bowl, using a hand-held electric mixer, beat the butter at 
  medium speed until soft and creamy. Add the sugar and lemon zest and 
  beat until the mixture is very light and fluffy, about 2 minutes. 
  Beat in the eggs, one at a time, and then beat in the vanilla. 
  In a medium bowl, toss the flour, baking powder and salt. Gradually 
  add the flour mixture to the butter, beating on low speed until a 
  smooth dough forms. Using a wooden spoon, work in the hazelnuts until 
  evenly distributed. 
  Divide the dough in half in the bowl. With lightly floured hands, 
  form the dough into two 10-by-2 inch rectangular logs. Place the logs 
  on an ungreased baking sheet, at least 2 inches apart. Bake for 30 
  minutes, or until the logs are set and golden brown. Remove from the 
  oven and let cool on the baking sheet for 15 minutes. 
  Using a serrated knife and a sawing motion, carefully cut the logs 
  into 1/2-inch diagonal slices. discard the end pieces. Arrange the 
  slices, cut sides down and close together, on 2 baking sheets. Bake 
  the biscotti on the top and middle racks of the oven for 8 to 9 
  minutes, or until lightly browned. Turn the biscotti over, switch the 
  position of the baking sheets and continue baking until lightly 
  browned on the other side, about 9 minutes longer. Let the biscotti 
  cool completely on the baking sheets.