A variation of the classic McDonald's Big Mac sandwich in which the standard hamburger patties are replaced by quarter-pounder burgers via special order.
This restores the sandwich to the original glory it enjoyed upon its introduction in 1968 before the burgers slowly shrank over decades until the present when they are dwarfed by White Castle patties.
Because the flimsy sesame seed buns haven't had a real burger placed on them in decades, the Fat Mac special order violates the use-as-directed warranty and may result in injury or Special Sauce spillage. For this reason it is customary to cut the sandwich into quarters and treat each fourth as if it were a dainty canape.
The Super-Size Fat Mac Value Meal is traditionally eaten in celebration of the breaking of one's diet.
Customer: "Gimme a Big Mac with quarter-pounder burgers value meal with large Coke. And I'm gonna go with a Fillet-O-Fish sandwich, since that has less calories 'cos it's fish."
Teller: "One Fat Mac meal, one Filet-O-Fish would you like to Super-Size that?"
Customer: "Oh yes."
Glutton 1: "Gater holy shit you ate three Fat Macs?!?"
Glutton 2: "Burp! Are you gonna eat those chicken nuggets?"
Glutton 1: "You are a Golden God!"