Preheat oven to 350F. Butter and flour a baking sheet and set aside. Whisk together flour, cocoa powder, baking soda, and salt. With an electric mixer, beat butter and sugar until fluffy. Add eggs; beat until well combined. Add flour mixture, and stir to form a stiff dough. Stir in pistachios and chocolate chips.

Transfer dough to prepared baking sheet; form into a slightly flattened log, about 12 by 4 inches.

Bake until a little bit firm, about 25 minutes.

Cook on a rack for about 5 minutes. Reduce oven temperature to 300F.

Cut biscotti diagonally using a serrated knife. Cut into 1-inch-thick slices. If you cut them too think, they may dry up and end up too hard. Careful when you cut since the biscotti may break.

Arrange biscotti with their sides down on a baking sheet and bake until crisp but still slightly soft in the center (about 8 minutes). This is key since you do not want to eat a biscotti that it is so hard you inevitably have to dip it in milk.

Once baked, put them in a rack and let them cool down.

I poured some white chocolate on top but they are perfect without it. This is definitely the best double chocolate pistachio biscotti I have ever had. (this is from the Kitchen of Martha Stewart)

Now that you have learned how to make double chocolate pistachio biscotti, please be sure to view these other chocolate recipes and these cookies recipes.