Pre-heat grill to 600° or there about. A good burger needs HEAT.

While grill is heating, break hamburger into small pieces then portion into 6 burgers, 1/3lb. each. Handle the burger gently. Do not press firmly together. Just push until the patty holds together and no more. A loose pack will allow for a more juicy burger. 

Sprinkle both sides of the burger generously with salt and pepper. Place on a plate in the fridge until the grill is ready.

When the grill is hot, place burgers on the grill and shut lid. Cook for 3 minutes. Flip burgers then cook, covered for 2 more minutes. Check the temperature of the meat with an instant-read thermometer, pull off at 125°. The meat will continue to cook as it rests on the plate. It will rise to 135° to be medium rare when you eat it. 

If you'd like your burger more done, continue cooking but test temperature every 30-45 seconds. It will cook fast. Pull the burger off the grill 10° before your desired doneness (so for well-done, pull at 145°.