It's described as a blend of cereal, peanut butter, chocolate, and powdered sugar.
Remember those old Reese's Peanut Buter Cup commercials, where a guy carrying chocolate bumps into a guy carrying peanut butter? Well, in this case there would have been a third guy carrying cereal, and all three of them falling into a giant vat of powdered sugar.
You can buy them online from Nancy's (look under "Nuts and Brittles")...
http://www.nancyshomemadefudge.com