Cream butter and sugar. Add eggs and vanilla. Mix well. Combine flour, baking powder, and salt; add to creamed mixture. Stir in vanilla chips, chocolate chips, and ½ C nuts. In sprayed 9 X 13 pan, spread dough to cover the bottom of pan. Sprinkle with remaining nuts. Bake at 350 for 25-30 min. or until golden brown. Let cool before serving.