Here are all the “secret” fast food menu items
We've talked about different items you can order at fast food joints that aren't actually part of the restaurants official menu. In n Out Burger is probably the most famous with their "animal style" toppings and the 4x4 burger. But there are "secret" items at a bunch of places. McDonald's has the "McGangBand" which is a double cheese burger with a chicken patty in the middle. You can get a pizza sub at Subway. And at Taco Bell they have the Superman Burrito: a cheesy double beef burrito loaded with potatoes, sour cream, guacamole, and tortilla strips. None of these items are on the stores official menu--just the secret menus.
Here's a website that has a ton of other ones from 15 different establishments.