Preheat the oven to 350 F. In a large bowl, mix butter and sugar together until smooth. Stir in the vanilla extract, and mix until smooth. Add in the flour, mix until it is fully combined.
Fold in the chopped up candy bars. Roll the cookie dough into balls and flatten slightly. Place the cookies onto a large ungreased baking sheet at least 2-inches apart. Bake for 10-12 minutes.