If making your own bacon onion jam, do that first. (See note below)
Shape your ground beef into 4 patties, about 1 inch thick, making them slightly thinner toward the middle to prevent shrinking.
Heat a griddle or cast iron pan over medium heat. Meanwhile, slice cheese, slice buns, and get other ingredients ready.
When griddle is hot, place on buns to toast for 2 to 3 minutes*. Season the burgers with 1/4 teaspoon each of salt and pepper.
Place burgers on hot griddle and let cook, without moving for 5 minutes. Meanwhile if your bacon jam isn't warm, heat gently in a sauce pan or microwave until warm.
Flip burgers and cook for an additional 5 minutes*. In the last three minutes, place the cheese on top of the burgers and cover with a lid or tent with foil to let the cheese melt.
While your burgers finish cooking, spread 1 tablespoon of mayonnaise on each burger bun and layer the bottom buns with greens.
When burgers are done, place on top of the leafy greens. Spoon two to three tablespoons of bacon jam on each burger and top with bun.
Serve immediately.
Notes
If you'd like to make your own bacon jam for the burgers, please see this recipe
*You can also toast the buns in a toaster or toaster oven. *5 minutes per side is for a medium burger. For medium rare reduce to 4 minutes per side, for medium well increase to 6, and for well done, to 7 per side.