I think this bit is totally up to each individual and the fun bit is putting out a selection of toppings and let everyone help themselves. If you want some cheese on top, add it to the burgers for the last minute so that it melts over the burger. I like to use Cheddar, Stilton, Edam or Emmental. Some great toppings include: fried onion slices crisp bacon grilled halloumi fried sliced mushrooms lettuce slices of beef tomato