Heat a large skillet or griddle to medium high heat. Add the onions and season with salt and pepper. Cook until the onions are softened and beginning to brown. Remove from the heat.

Divide the beef into 4 loose rounds. Place the burgers on the pan. Once juices start to pool at the bottom of the burger use a smash burger press or large metal spatula to smash the burger until it is SUPER THIN! Season with salt and pepper. Once you see juices pooling on the meat flip the burger. Add the cheese and cook for an additional minute. Toast the buns on the hot griddle. Build the burgers by topping each bottom bun with onions, a burger patty, and then smearing the top bun with Wisconsin Butter. Top the burger and enjoy.