Dark chocolate and pistachios go very well together.
18 tablespoons margarine, softened at room temperature (2 ¼ sticks)
6 cups flour
1 ½ cups unsweetened cocoa powder
2 teaspoons baking soda
1/2 teaspoon kosher salt
3 cups sugar
3 cups shelled pistachio nuts (not salted)
1 1/2 cup chocolate chips
1 pound (16 ounces) baking chocolate or cookie dip for coating
Heat oven to 350 degrees. Line two baking sheets with silpat mats or parchment paper; set aside.
In a medium bowl, whisk together flour, cocoa powder, baking soda, and salt.
In the bowl of an electric mixer, cream margarine and sugar until light and fluffy. Add eggs; beat until well combined, scraping down sides of bowl if necessary. Add flour mixture, and stir to form a stiff dough. Stir in pistachios and chocolate chips.
Divide dough in half and divide each half into three. Transfer dough to prepared baking sheet; form each part into a flattened log, about 10 by 3 inches. Bake until slightly firm, about 20-25 minutes. Cool about 5 minutes. Reduce oven to 300 degrees.
Transfer biscotti to a cutting board. Using a sharp serrated knife, cut biscotti diagonally into 1-inch-thick slices. Arrange biscotti, cut sides down, on baking sheet, and bake until crisp but still slightly soft in the center, about 7-8minutes. Remove from oven and cool 10 minutes.
Chop baking chocolate and melt in a double boiler or microwave. Prepare a cooling rack on your counter top over some foil or parchment paper.
Dip each slice of biscotti diagonally into the melted chocolate. Place on the cooling rack to dry. Allow to dry 30 minutes. Store airtight for 4 days or freeze.