Make vanilla pudding according to the directions on the package for a pie. Use a double boiler. Mix together the peanut butter and egg yolks. Then add to the pudding mix, stirring for 10 minutes keeping the lumps out. Remove from heat. Add the butter and cool. Stir in vanilla. Pour in the pie shell. Sprinkle the chips on pie. Top with meringue. Bake 1520 minutes at 300 degrees until golden brown. Tastes best when served cold. Serves 6-8.