Cook bacon on a griddle until browned and crisp, about 4 minutes per side. Remove to a paper towel lined plate.

Form the meat into 6 balls and refrigerate for at least 15 minutes - the meat needs to be very cold. Heat a cast-iron skillet or griddle over medium-high heat. You want the griddle surface to be approximately 400 degrees F.  Place 2 very cold meat balls on the skillet and immediately smash flat with a burger press or large spatula. Use a metal spatula to carefully remove the press from the burger. Sprinkle with salt and pepper and cook until a nice crust is formed, about 3 minutes. Flip and top each burger with 1 slice of cheddar cheese. Cook until meat is browned and cheddar cheese is melted, about 2 more minutes. Toast 1 bun on the griddle while the cheese melts. Stack the burgers and place on the bun. Top with 2 slices of bacon and desired condiments. Repeat with the remaining ingredients to make 3 burgers.