With puréed pumpkin, rich cashews, and warm winter spices layered into the dough, these crunchy biscotti make a terrific holiday gift or addition to the brunch table.
Preheat the oven to 350 degrees. In a large bowl, whisk together brown sugar, pumpkin, vanilla, and eggs until well combined. In a second bowl, whisk together flour, cashews, pumpkin pie spice, baking powder, and salt. Add pumpkin mixture to flour mixture and stir until just combined.
Using slightly damp hands, shape dough into 3 (6-by-2 1/2-inch) logs and arrange on a large, parchment-paper-lined baking sheet, spacing them a few inches apart. (This will result in medium-size biscotti. For smaller cookies, shape into 8-by-2-inch logs.) Bake until just firm and golden brown, about 25 minutes. Set aside to let cool for 10 minutes; reduce oven temperature to 300 degrees.
Using a serrated knife, cut each log crosswise into 1/2-inch-thick slices. Arrange on 2 large, parchment-paper-lined baking sheets and bake, rotating the baking sheets and flipping biscotti every 10 minutes or so, until dried out and just crisp, 30 to 35 minutes. Let cool completely, and then serve. Store in an airtight container for up to 2 weeks.