Preheat the oven to 350 degrees. Line baking sheets with parchment for easy cookie removal.
In a medium mixing bowl, cream the butter and sugar with a hand mixer. Add the egg and egg yolk, mixing well to combine then add the vanilla and mix well.
With the hand mixer on a low speed, add in the flour and salt. Combine completely then mix the white chocolate chips and macadamia nuts by hand with a spatula.
Drop spoonfuls or scoops of dough onto parchment lined baking sheets. Leave about 2 inches between cookies to allow for spread while baking.
Bake for 12 minutes, remove from the oven and let cool on the baking sheet before removing them. It is okay if they still look a little wet or shiny on top, go ahead and remove them from the oven.
The cookies will crumble and fall apart if you try to move the cookies before they cool. This is very common with gluten free cookies especially. Once they have cooled, they will be beautifully crispy on the outside and chewy in the middle. Enjoy!