Burgers Patties: Preheat the barbecue to medium-high heat.
Place the mince in a large bowl then add the salt and pepper. Gently and briskly toss and mix the beef mixture together, but do not squeeze or overmix.
Divide the mince into 4 portions, and gently form into 4 burgers, about 2cm thick. Take your thumb and press a slight indentation in the centre of each. Lightly coat each burger with a bit of olive oil.
Place the burgers on your BBQ's grate, indentation side facing up. Cover the barbecue and sear the first side for 3 minutes. Flip the burgers, then cover, and cook to your desired doneness - about another 3 to 5 minutes. Add a slab of blue cheese to each burger for the last 2 minutes of cooking.
Remove the burgers from the BBQ, and tent with aluminium foil for a couple of minutes. This will keep them warm and lock in the juices.
To Assemble: Toast your buns on the grill. Place a dollop of onion chutney on each, then top with the burger. Serve straightaway.
Resist the urge to press the burgers while they're cooking, as this will release all of the lovely juices and make your burgers disappointingly dry!
Also, don't overwork the mince, as this results in heavy and dense burgers.