Preheat the oven to 350°F.

In a medium bowl, whisk together the all-purpose flour, baking powder, and salt.

In the bowl of an electric mixer, beat the granulated sugar and room-temperature butter together until smooth and fluffy, about 3 minutes.

Stir in the eggs, one at a time, ensuring each is fully incorporated before adding the next.

Stir in the vanilla extract.

Gradually add the dry flour mixture into the wet ingredients, stirring until just combined.

Gently fold in the coarsely chopped macadamia nuts and the semi-sweet chocolate chips.

Divide the dough evenly in half.

Wrap each half tightly in plastic wrap and place them into the freezer to chill for 20 minutes. (This prevents the logs from spreading too much while baking).

Remove the chilled dough from the freezer.

Use your hands to form each piece of dough into a log, measuring about 12 inches long and 3 inches wide.

Place both logs onto a baking sheet lined with a Silpat mat or parchment paper, leaving space between them.

Bake in the 350°F oven until the logs are firm and golden brown, about 20 minutes.

Remove the baking sheet from the oven.

Immediately reduce the oven temperature to 300°F.

Allow the baked logs to cool on the baking sheet for exactly 15 minutes.

Carefully transfer the logs to a cutting board.

Use a sharp serrated knife to cut each log into diagonal ½-inch thick slices.

Lay the slices flat, cut-side down, back onto the parchment-lined baking sheet.

Return the pan to the 300°F oven.

Bake until the biscotti slices are deeply golden and dry to the touch, about 30 more minutes.

Transfer the finished biscotti to a wire rack to cool completely before serving.