Preheat your oven to 350°F (175°C). Line a large baking sheet with parchment paper.
In a large mixing bowl, add the sugar and orange zest. Rub them together with a spatula to release the orange aroma.
Add the eggs and whisk until well combined and slightly frothy.
Whisk in the olive oil, salt, and baking powder until fully incorporated.
Add the flour and mix until the dough comes together—avoid overmixing.
Gently fold in the whole pistachios until evenly distributed throughout the dough.
Divide the dough into two equal portions. Place each portion on the prepared baking sheet.
Lightly dust with flour and shape into two long logs. Flatten the tops so they are no more than 1 inch thick.
Bake the logs at 350°F (175°C) for 20 minutes, or until lightly golden.
Remove from the oven and let them cool on the baking sheet for 5 to 10 minutes.
Transfer the logs to a cutting board. Using a sharp knife, slice them into ½-inch pieces.
Arrange the biscotti slices on the baking sheet, cut side down. Bake for 10 to 15 more minutes, flipping them halfway through.
Let the biscotti cool completely on a wire rack.
Melt the white chocolate in the microwave or a double boiler. Drizzle the chocolate over the cooled biscotti.
Place them on parchment paper and refrigerate briefly to set the chocolate
.
