Step 1: In a medium bowl, whisk together the all-purpose flour, baking soda, and salt. Set aside.
Step 2: In a large bowl, using an electric mixer, cream together the softened unsalted butter, granulated sugar, and packed light brown sugar on medium speed until light and fluffy (about 2-3 minutes).
Step 3: Beat in the large eggs, one at a time, mixing well after each addition. Stir in the vanilla extract until just combined.
Step 4: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Do not overmix.
Step 5: Fold in the chopped, toasted macadamia nuts until evenly distributed.
Step 6: Cover the bowl with plastic wrap and refrigerate the dough for at least 30 minutes, or up to 24 hours. This helps prevent spreading and enhances flavor.
Step 7: Preheat your oven to 375°F (190°C). Line baking sheets with parchment paper or silicone mats.
Step 8: Scoop rounded tablespoons of dough onto the prepared baking sheets, spacing them about 2 inches apart.
Step 9: Bake for 9-12 minutes, or until the edges are golden brown and the centers are still slightly soft. Do not overbake.
Step 10: Remove from the oven and let the Macadamia Nut Cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.