Preheat the oven to 325 degrees F. Line cookie sheets with parchment paper or use the Silicone Baking Mats to prevent the cookies from sticking.
In a mixing bowl, using your electric mixer fitted with the flat beater, cream the butter, brown sugar, and granulated sugar together until smooth. Add the eggs, one at a time, waiting before the first is incorporated before adding the second. Mix in the vanilla extract.
In another bowl, combine the flour, baking powder, baking soda, and salt; gradually stir into the creamed mixture. Using a rubber spatula, fold in the white chocolate and macadamia nuts by hand.
Scoop out approximately 2 tablespoons-sized balls of dough and drop them at least 2-inches apart on the prepared baking sheets.
Bake on the center racks in the oven for approximately 10 to 13 minutes, or just until the cookies begin to turn golden. Don't over bake as these cookies should be soft and chewy. Remove from oven and let cool on the cookie sheet for 3 minutes, and then transfer to wire cooling racks.
* If you can only find salted macadamia nuts, place the nuts in a sieve and wash them. Spread them out on a paper towel to dry before using.
White Chocolate Macadamia Nut Cookie Recipe: https://whatscookingamerica.net/cookie/whchocmacadamia.htm