These are very delicious. Confectioner sugar and lemon juice is used for glazing these biscotti.

Ingredients
All purpose flour (2c), baking powder (1tsp), granulated sugar (1/3c), unsalted butter (1/2c), eggs (2large), grated lemon zest (2tsp) and salt (tsp)
For glaze- Confectioner sugar (1c) and strained lemon juice (3tbsp).

Method of preparation:-
First heat the oven to 350 degrees F. Take a bowl. Mix flour, baking powder, granulated sugar and salt in it. Rub these ingredients in butter with fingers or pastry blender. Blend these until look like cornmeal. Take a bowl, mix eggs and lemon zest. Add flour mixture in it. Mix it with fork and make the dough of this mixture. Place the dough on work surface and knead it. Now divide dough in 2 equal parts. Roll each in cylindrical shape about 12 inches long. Place these on baking sheet and cover with buttered aluminum foil or with parchment paper. Now flat them with hand about 1/ 2inch thick. Place baking sheet in oven and bake it for 30 minutes at 325 degrees F until get golden and firm to touch. Take off the sheet from oven and cool. Place on cutting board and cut into diagonal slices of 2 inches wide. Place these slices on baking sheet wit cut side down. Bake for 20 minutes until golden in color. Take off biscotti from oven. Take a pan, prepare glaze in it by adding confectioner sugar and lemon juice in it and cook over low heat until it gets bubbly. Then brush this on warm biscotti.
Make about 4 dozen biscotti.