I've seen burgers that have so many toppings on them that there is no way you could taste the meat - and isn't the the point of having a burger? I think that what you put on the patty should only enhance the flavor of the meat not distract from it. I personally like grilled onions on my burgers because I think it helps the taste with the meat. Sometimes I put some mustard on there, but not much. What are your favorite toppings and why?