Use ground beef with 80/20 fat content
Form loose meat balls, about 2 to 3 ounces each
Heat a cast iron skillet or griddle over high heat
Add a small amount of oil or beef fat
Place the meat balls on the hot surface
Smash each ball firmly with a spatula or burger press
Season with salt and pepper immediately
Cook until the edges are deeply browned and crispy
Flip once
Add cheese if desired
Cook the second side briefly until done
Toast the buns on the skillet
Assemble with your preferred toppings and sauce
Serve immediately