In a large mixing bowl cream butter, brown sugar and sugar until light and fluffy. Add in eggs and vanilla and beat well. Gradually add in flour, baking powder, and salt and mix well. Fold in chocolate chips, white chips, and macadamia nuts.
Pour into a greased 9 x 13 inch pan and spread out evenly.
Bake for 25 to 30 minutes. Should be golden brown. Cool and cut into bars.