Heat oil and butter in a large non-stick pan, add burger patties into the pan and cook for 2 -3 minutes on each side, then reduce the heat, top with sliced camembert cheese and cover with a lid, let this cook further for about 1 – 2 minutes until the cheese starts to melt, then remove from the heat and set aside.
To assemble the burgers spread some mayonnaise of the toasted burger buns, then top with lettuce, tomatoes burger patties and lastly a dollop of caramelised onion chutney.