1Heat oven to 375°F. Line large cookie sheet with foil. In medium bowl, stir cookie mix, butter and egg until soft dough forms. Press dough into 12-inch square on cookie sheet.
2Bake 10 to 14 minutes or until light golden brown; cool.
3In microwavable bowl, microwave white vanilla baking chips uncovered on High 30 to 60 seconds, stirring every 30 seconds, until chips can be stirred smooth. Pour and spread over cooled cookie base. Immediately sprinkle with candy. Let stand until set, about 30 minutes.
4Gently break up cookie bark. Store tightly covered.