Preheat oven to 325 degrees. Grease a jelly roll pan (this is the bakers half sheet size - it’s like 11 1/2 inch x 16 1/2 x 1 or you could use 2 9×13 inch pans. The pie may be a little thicker and may take a little longer to cook).
In a large bowl, combine sugar and melted butter; beat with electric mixer. Add eggs, one at a time, and vanilla; mix well.
Combine flour and baking powder in a separate bowl. Add to the sugar mixture; mix well.
Stir in nuts, coconut, and white chocolate chips. Pour batter into prepared pan.
Bake 40+ minutes until a toothpick inserted in the center comes out clean.
Serve warm, or reheat individual servings in the microwave (10 seconds for a serving). Top with ice cream drizzled with caramel sauce then sprinkled with chopped macadamia nuts. Or just eat them like a brownie or bar cookie. They are also excellent that way too. Makes 24.