Question: What toppings are on a Mexican burger?
About the article "Hamburger", section "Mexico".

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Myriad toppings are used on pizzas, including, but not limited to: 
During the game, hamburgers go through an oven and are placed on a conveyor belt headed in the player's general direction.
In order to satisfy customers' orders (seen on a chart at the bottom of the screen), the player must catch the flying toppings for a particular order and place them on the burger.
Once a burger is assembled, the player must catch the top bun, place it on the burger, and then drop the completed burger into the proper colored slot.
Once all the slots are filled, the level ends, and the player receives bonus points for remaining performance points (see below) and for every burger successfully completed. 
The BK Stacker sandwiches are a family of hamburgers featuring the same toppings that targets the late-teen–to–young-adult and male-oriented demographic groups.
It is a cheeseburger consisting of anywhere from one to four grilled beef patties, American cheese, bacon and Stacker sauce served on a sesame seed bun. 
Main dishes.
Harvey's is known for its grilled burgers, allowing customers the choice of 11 different toppings, including lettuce, pickles, tomatoes, onions, chili peppers, and a wide selection of condiments ranging from ketchup, mustard, BBQ sauce, mayonnaise to Frank's Red Hot sauce.
Cooked burgers are placed in view of the customer, behind a glass counter, while an employee garnishes the burger according to the customer's wishes before wrapping it in paper and serving it to them.
In this sense, Harvey's is closer to the model used by submarine sandwich chains like Subway, as opposed to other burger chains which use a set list of toppings for each burger, omitting toppings only at the customer's specific request.
Harvey's claims that in 1998, they were the first to introduce "Custom Combos", allowing customers to modify their combo with different items from those usually included.
For example, one could get a salad instead of fries or a milk carton instead of a soft drink.
Aside from beef burgers, Harvey's also offers hot dogs, veggie burgers, and grilled chicken burgers, all which can be topped as desired by the customer.
Chicken strips and salads (with or without chicken) are also available.
In the third fiscal quarter of 2006, Harvey's discontinued items such as specialty burgers, deli sandwiches, Caesar salad, and value-priced burgers.
The hamburger menu at the time was simplified to six basic varieties: original hamburger, original cheeseburger, original bacon cheeseburger, and double-patty versions of each.
The current version of the menu lists cheese and bacon as premium toppings rather than as part of a burger, meaning that only the Original Burger and Double Original are listed as hamburgers.
Three alternative sandwiches were kept on Harvey's revised menu: one with grilled chicken, one with crispy chicken and a veggie burger. 
The bulk of the secret menu revolves around the burgers.
In-N-Out's own website acknowledges the existence of this secret menu, publicizing "some of the most popular items" on what it calls the company's "not-so-secret menu.
""Animal Style" is one of the most popular "secret" styles; in addition to the standard toppings, Animal Style burgers include pickles, extra spread, grilled onions, and mustard fried onto each meat patty.
"3×3" (pronounced 3-by-3), "4×4", or variations of "m" × "c", refers to a burger with a varied amount of meat patties, "m", and slices of cheese, "c": e.g.
a burger with six meat patties and three slices of cheese is a "6×3".
The In-N-Out "secret menu" section of the website only mentions the "3x3" and "4x4", which are registered trademarks of the company.4x4 is the largest burger that In-N-Out currently makes.
However, there have been instances of much larger sandwiches.
On October 31, 2004, a group of friends ordered a 100x100 from a location in Las Vegas, Nevada, posting photos on the web of the burger.
In-N-Out has two low carbohydrate offerings, akin to the Atkins diet.
"Protein Style", introduced in the 1970s, replaces the bun with large leaves of lettuce; while the "Flying Dutchman" is a 2x2 with no bun, no vegetables, and no spread.
Unless a variation adds meat or cheese, the price is the same as a regular menu item.
Other secret menu items include:  Grilled Cheese - "Two slices of melted American cheese, hand-leafed lettuce, tomato, spread, with or without onions on a freshly baked bun."
Veggie Burger - A sandwich containing only vegetables, without beef or cheese.
Chopped Chilies - Chopped yellow chili peppers are added to the burger.