Combine butter, cream cheese, and brown sugar in mixing bowl. Beat for a few minutes until well mixed.
Add corn syrup, vanilla extract, peanut butter, and powdered sugar. Mix until combined.
Stir in chocolate chips.
Cover and chill for 2 hours. After, form into ball or spoon into serving dish and chill. Serve with graham crackers, vanilla wafers, chocolate cookies, etc.
Promptly refrigerate leftovers.