When it comes to hamburger toppings, the sky's the limit.
Common ingredients include fresh vegetables, cheese, mushrooms, and bacon.
Homemade hamburgers should try to have more fresh vegetables than the token slices offered by fast food joints. Hamburgers can be healthy good eats when fresh vegetables and fruits are added. The key word is freshness. Nothing taste worse than a wilted lettuce leave or sour tomato.
Popular fresh vegetables include onions, lettuce and tomato. These fresh vegetables provide balance against the meat. Avocado is becoming increasingly popular.
All sorts of cheese has been used as hamburger toppings. Cheddar is the most common but others like mozzarella, buffalo, swiss, blue cheese, brie and etc. There are also bacon and eggs. These are great paired with patties that are leaner.
Mushrooms are not really vegetables but they are really great in burgers.
Toppings vary from place to place.
Every region of the United States has a different "standard" hamburger, and a different regional specialty. What is common in one area might be unheard of in another.
Burgers from Texas may feature mustard and jalapenos. A Midwestern burger will often include butter (generally in the form of a buttered bun), while eateries in North and South Carolina might eschew the traditional toppings entirely and use chili and coleslaw.
Hawaiian burgers generally stick with an asian theme; using teriyaki sauce and pineapple, while California might add guacamole.
The Southwest is home to a popular concoction called the "Slopper", which features judicious use of red and green chilis.
International variations are even more mind-boggling.
What do you normally top your burger with?