Preheat oven to 350℉/176℃ and line two baking trays with parchment paper and set aside. Melt the butter and allow it to cool as you prep the rest of the ingredients.
1/2 cup unsalted butter
Combine flour, baking soda, baking powder, cornstarch, and salt in a bowl. Set aside.
1 1/2 cups all-purpose flour, 3/4 tsp baking soda, 1/4 tsp baking powder, 1/4 tsp salt, 2 tsps cornstarch
Whisk together butter, brown sugar, and white sugar until well combined (1-2 minutes).
1/3 cup dark brown sugar, 1/2 cup white sugar, 1/2 cup unsalted butter
Add in egg and vanilla and continue whisking.
1 large egg room temperature, 2 tsps vanilla
Mix in the dry ingredients gently just until a soft cookie dough forms. Don't over-mix!
Mix in the chopped macadamia nuts and chocolate. Stir a few times to combine.
1/2 cup macadamia nuts*, 1/2 cup white chocolate chips*
Scoop 6 cookies at a time, placing them evenly apart from one another.
Bake for 11-15 minutes or until the edges are golden brown and the middles are slightly puffy and underbaked. The middles will continue to bake as they cool.
Allow to cool, and enjoy!