1 Preheat the oven to 350ºF. Line 2 baking sheets with parchment paper.
2 Combine dry ingredients: In a large bowl, sift the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Stir in the orange zest, cranberries and pistachios until combined.
3 Whisk together the eggs and vanilla, in a separate bowl.
4 Make the dough: Add the eggs to the bowl of dry ingredients and stir until blended. Use your hands as necessary to bring the dough together, mixing until no more dry flour remains.
5 Shape the dough: On a lightly floured surface, turn out the dough and divide it in half. Shape each half into a log roughly 12 inches long and 2 inches wide. Place the logs about 4 inches apart on one of the baking sheets.
6 Bake the biscotti logs: Bake the logs for 30 minutes, rotating the pans halfway through. When done, the logs should be risen and slightly firm. (They will still be a little soft in the center and that’s ok.)
7 Cool the logs for 10 minutes: Slide the logs, still on the parchment, onto a wire rack to cool for 10 minutes. The logs should still be warm and a little soft. Do not let the logs cool for longer or they become to crisp and brittle to slice neatly.
8 Slice the logs into biscotti: Transfer the logs to a cutting board. Use a serrated knife to cut the logs into slices roughly 1/2-inch thick – cut at a right angle for small biscotti or at a sharp angle for larger biscotti.
Transfer the biscotti to the baking sheets. Arrange the cookies close together, but without touching.
9 Bake the cookies: Bake for 8 minutes. Turn the slices over and continue baking for 5 to 6 minutes longer, or until the biscotti are firm and dry. Cool on a wire rack.
The finished biscotti will keep for 2 weeks in an airtight container, but I doubt you will have them around that long. The baked cookies will also freeze well for up to 3 months.