Preheat the oven to broil.
Butter the tops and bottoms of the buns.
Broil them until they are golden brown.
Remove them from the oven and set them aside.
Turn off oven.
Brown the ground beef in a large stove-top skillet
When it is half way cooked, add the diced onions and Worcestershire sauce.
Cook the meat and onions until the beef is browned.
Pour off the excess liquid.
Turn the burner on medium low.
Salt and pepper the sloppy joe mixture.
Stir in 4 TBS of the Big Mac sauce.
Stir in the shredded cheese.
Stir the sloppy joe mixture until the cheese if melted.