Why does Filet-o-Fish only have a half-slice of cheese?

We go by the same Filet-O-Fish® recipe one of our franchisees came up with way back when in 1961. Who knew, right? Of course, you can always ask for 'extra' cheese the next time you order a tasty Filet-O-Fish® at your local McDonald's. It’s the 21st Century, after all.