In a pan over medium-high heat, add the bacon, and cook until crispy. Transfer to a cutting board and roughly chop.
In a bowl, add the bacon, cream cheese, green onions, and shredded cheddar. Mix well.
Divide the ground beef into four even portions and shape into balls. Form a well into the center of each, large enough for the cheese mixture.
Place a quarter of the cheese mixture into the center of each ball, and enclose inside the ground beef. Gently press each ball into a patty shape, and season both sides generously with salt and pepper.
Heat a cast-iron pan over medium-high heat. Once hot, add the burgers and cook for 4-5 minutes on one side.
Flip the burgers, and cook for 2 minutes. Add a slice of cheese on each burger and cook for an additional 2 minutes, until the burger is cooked through and the cheese is melted.
Remove burgers from pan, and place on top a toasted burger bun. Top with condiments of your choice.