4 Tbsp Butter
16 Slice White Bread
16 Slice (3/4 oz) American Cheese
16 Oz Ground Beef
1 Dash Salt
1 Dash Pepper
4 Tbsp Ketchup
Preheat oven to 350 degrees F.
Spread butter evenly on one side of each bread, then place buttered side in a cast-iron skillet over medium-high heat until golden brown.
Transfer to a large sheet pan with toasted bread side face down and place 2 pieces of American cheese on each piece of bread.
Preheat same cast iron pan over high heat.
In a mixing bowl, add cold ground beef and season with salt and pepper.
Divide into 1/4-pound burgers and form 1/2"-thick, square-shaped patties, similar to bread dimensions.
(Avoid over-handling the burgers as it will make them tough.
) Cook burgers in two batches.
Flip burger after about 2 minutes, then cook 2 minutes more (or until burgers have reached desired doneness).
Transfer to a plate and loosely cover with aluminum foil; rest 2 minutes.
Meanwhile, place sheet pan with bread in the oven until cheese is just melted.
Lightly blot burgers with a paper towel.
Place burgers on toasted bread with cheese and top with second piece of bread.
Return grilled cheese burgers to the cast iron pan to warm the bread.
Serve immediately while warm with ketchup, if desired.