Portion the wet ingredients (egg, vanilla and milk) in another bowl, set aside.
Cream the butter and sugar in your mixer on a medium speed. Add the wet ingredients to the butter mixture in three stages. Mix until fully incorporated for each stage. When the last of the wet is incorporated, turn the mixer off.
Add the dry ingredients all at once. Mix on speed 1 just until the dough starts coming together. Give it a 5 second flash on a medium-high speed, to insure the mixture is homogeneous.
Toast macadamia nuts and sweetened coconut in 375 degree F oven for 10-15 min, stirring halfway through. Pulse through food processor to roughly chop. Mix into cookie dough.
Drop cookie dough by tablespoonfuls onto ungreased cookie sheet. Bake for 15 to 16 minutes in 375 degree F oven or until edges are light golden brown. Remove from oven and cool 1 minute.
Melt white chocolate chips in microwave in 1 minute intervals at 50% power, stirring each time, until smooth. Drizzle over cookies.