Preheat oven to 350°F. Line a 9x9" pan with foil and spray with nonstick cooking spray.

Break up cookie dough in a large bowl. Stir in apples, cinnamon, and toffee. You may need to use your hands to get it completely mixed. Press dough into prepared pan.

Bake 20-30 minutes or until the cookies are browned and cooked through. Cool completely before making frosting.

To make the frosting: heat butter in a small saucepan over medium low heat. Add the brown sugar and milk and cook until the mixture boils. Remove it from the heat and stir in the powdered sugar and vanilla. Pour immediately over cooled bars. Let set, then cut and serve.

Store in an airtight container for up to 2 days.