In a mixing bowl, cream butter & sugars.
Add eggs and vanilla; mix well.
Combine flour, baking powder and salt, add to creamed mixture and mix well.
Stir in vanilla chips, choc. Chunks and ½ c nuts.
Spoon into a greased 13x9x2 baking pan, spread evenly to cover the bottom.
Sprinkle with remaining nuts.
Bake at 350º for 25-30 min.