For the burgers: Fire up the grill for cooking on high heat (1 to 2 seconds) and then on medium heat (4 to 5 seconds).
Mix together the ground chuck, salt and pepper. Gently form the mixture into six patties ½- to ¾-inch thick. Avoid handling them any longer than necessary.
Grill the burgers uncovered over high heat for 1 minute, 30 seconds per side. Move the burgers to medium heat and rotate a half turn for crisscross grill marks. Do not mash the burgers with the spatula! Cook about 4 minutes longer, then turn once more and cover each burger with cheese. Cook another 4 minutes for medium doneness (145 degrees).
To assemble, smear buns with ketchup or mayo. If you’re using tomato or any of the other optional toppings, arrange on each bun next. Follow with cheese- covered burgers. Spoon chile over each. Crown with bun tops.