Preheat oven to 350*. Line 2 baking sheets with parchment paper.
In large bowl, combine flour, 1/3 cup of sugar, baking powder, baking soda, and salt. Using a pastry blender,(confession time, I use my fingers) cut in butter until mixture resembles coarse crumbs. Add white chocolate chips and nuts; mix well.
In another bowl, whisk together buttermilk,egg,and vanilla extract. Add butter milk mixture to flour mixture, stirring until dough is just combined.
Drop by heaping teaspoonsful onto prepared baking sheets. Sprinkle with remaining sugar. Bake for 14 to 16 minutes till lightly browned. enjoy