Hamburger Cheese (usually processed cheese slices but often Cheddar, Swiss, pepper jack, or blue), either melted directly on the meat patty or crumbled on top, is generally an option. Condiments might be added to a hamburger or may be offered separately on the side including mustard, mayonnaise, ketchup, salad dressings and barbecue sauce. Other toppings can include bacon, avocado or guacamole, sliced sautéed mushrooms, cheese sauce, chili (usually without beans), fried egg, scrambled egg, feta cheese, blue cheese, salsa, pineapple, jalapeños and other kinds of chili peppers, anchovies, slices of ham or bologna, pastrami or teriyaki-seasoned beef, tartar sauce, french fries,
Hamburger onion rings or potato chips. In Mexico, burgers (called "hamburguesas") are served with ham and slices of American cheese fried on top of the meat patty. The toppings include avocado, jalapeño slices, shredded lettuce, onion and tomato. The bun has mayonnaise, ketchup and mustard. In certain parts are served with bacon, which can be fried or grilled along with the meat patty. A slice of pineapple is also a usual option, and the variation is known as a "Hawaiian hamburger". Some restaurants' burgers also have barbecue sauce, and others also replace the ground patty with sirloin, Al pastor meat, barbacoa