In an oven preheated to 400°F, cook the bacon on a cooking sheet for 15–20 minutes.
Mix the two pounds of ground beef. Form into 3 10-ounce patties.
Salt and pepper the burgers liberally on both sides and sear on the hot side of the grill.
Turn the burgers ¼ after 2 ½ minutes. Cook for another minute as the edges start to brown before flipping to the other side. Cook for another two and half minutes. Turn ¼, add bacon and cheese.
Cook for another minute and let it rest for a few more minutes until it reaches an internal temperature of 145–150°F for medium.
Brush the buns with whole butter and toast for a minute on the cooler side of the grill.
Break off a few leaves of the lettuce to make a bed for the burger. Slice the beefsteak tomato into thick slices and the red onion into thin slices. Coat buns with the sauce, add bacon cheeseburger, and stack with lettuce, tomato, and onion.