Makes 4 burgers
1. In a large bowl, mix the ground beef with the salt and pepper.
2. Divide the meat into 4 portions (about 6 ounces each). Form each portion into a ball by gently tossing it from one hand to the other and then flatten each portion into a patty. Make the patty as thick or thin as you would like.
3. Heat the oil in a large cast-iron or stainless steel skillet over medium-low heat for 3 to 5 minutes. Add the patties to the hot pan and cook, flipping once, until well browned on each side, about 5 minutes per side. Ground beef needs to be cooked until the juices run clear when you pierce a burger with a knife and the meat reaches an internal temperature of 160°F.
4. If you are using cheese, top the hamburgers during the last 2 minutes of cooking so the cheese can melt.
5. To serve the burgers, place them on the buns and top each one with tomato, lettuce, mustard, and ketchup.