Oil the grill racks. Preheat your grill using all burners set on high and with the lid closed for 10 to 12 minutes.
Put the meat in a medium bowl and season with salt and pepper; go light on the salt here because we’re going to add more. Carefully, being as tender as you possibly can, use your hands to mix the seasonings into the meat and then form it into 6 patties that are 1/4 to 1/2 inch thick and slightly wider than the buns you intend to use. Take your thumb and make a good depression in the middle of each burger. Season the patties with salt and pepper. Slather some butter on the cut side of your hamburger buns.
Place the burgers on the grill, close the lid, and cook for 4 to 6 minutes. Turn the burgers and cook for an additional 4 minutes for a medium-pink doneness. If you want a well-done burger, cook for 12 to 15 minutes. They should start to feel firm when pressed. If you want to use an instant-read thermometer, do like the health inspectors do and go in through the side, not the top.
If you feel your burger is not complete without cheese, then add a slice to each patty during the last 2 minutes of cooking time. The cheese should melt nicely but not turn to liquid, and will continue to melt even after you take the burger off the grill.
During the last minute of the cooking time, add your buns to the grill, cut side down, and grill until lightly toasted.
Hamburgers are best served straight off the grill, into the bun, into your mouth. If the burgers are going to have to sit for a few minutes, place them on one platter and the buns on another instead of inserting the burger between the buns. Top each burger with tomato and lettuce, and dress with the condiments of your choice.