Brown half the butter and mix with the other chilled half. allow it to melt and cool.
Mix with sugars, then whip in the eggs and vanilla. mix on medium-high speed until pale and creamy.
Mix in the dry ingredients and then the white chocolate and nuts. it should be a very thick dough.
Scoop onto a large baking sheet lined with parchment paper. press to very slightly flatten & bake.
Allow to cool and dig in! they're perfectly soft, dense, and chewy with loads of chocolate & nuts.