In a bowl, sift together the flour, baking powder, baking soda and salt.
In a large bowl, whisk together the eggs, oil, honey, sugar, vanilla and orange zest. Add the flour mixture and stir to combine. Stir in the almonds and dates. Cover the bowl and refrigerate the dough for at least 2 hours.
Preheat an oven to 350°F. Line 2 baking sheets with parchment paper.
Divide the dough in half. With wet hands, shape each portion into a thin log about 15 inches long and 2 inches wide. Place the logs on one of the prepared pans, spacing them evenly (they will spread quite a bit). Lightly brush the tops and sides with the egg mixture. Bake until golden, about 20 minutes. Transfer the pan to a wire rack and let cool for about 15 minutes.
Cut the logs crosswise into slices about 1/2 inch thick. Carefully lay the slices, cut side down, on the prepared pans. Position 2 oven racks evenly in the oven and reduce the temperature to 325°F. Bake the biscotti until toasted and crisp, about 15 minutes, turning the biscotti once and rotating the pans about halfway through baking. Let the biscotti cool on the pans for 5 minutes, then transfer to wire racks and let cool completely. Makes about 4 dozen biscotti.
Baker’s note: Be sure to chill the dough so that it firms a bit before shaping the logs. Wetting your hands before working with a sticky dough also helps ensure that you don’t stick to it.Servings: