Preheat the oven to 350°F. Line baking sheets with parchment paper.
In a medium bowl, whisk together the flour, baking soda, and kosher salt. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment, cream the unsalted butter, light brown sugar, and granulated sugar on medium speed until the mixture is light and fluffy. This will take 3-5 minutes. Stop to scrape down the sides of the bowl as needed.
Add the eggs one at a time, mixing well after each addition. Mix in the vanilla extract until fully incorporated.
Add the dry ingredients to the wet ingredients and mix on low speed until just combined. Avoid overmixing to keep the cookies tender.
Gently fold in the white chocolate chips and chopped macadamia nuts.
Using a 2-tablespoon scoop, portion the cookie dough onto the prepared baking sheets, spacing them about 2 inches apart.
Use the flat bottom of a kitchen glass to slightly flatten each scoop of dough.
Bake for 9-10 minutes, or until the edges of the cookies just start to turn golden brown. The centers will still appear soft but will set as they cool.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.