heat a cast-iron griddle until very hot.

without overworking the meat, loosely form it into 4 balls and place them on the griddle.

season with salt & pepper

press a handful of sliced onions onto each patty.

using a sturdy large spatula, flatten each ball into a 5-inch round patty.

cook for 3 minutes, until well seared.

using the spatula, carefully flip each burger so the onions are on the bottom.

top with the cheese and cook for 2 minutes.

cover with the buns and add a couple of drops of water or beef broth if you have it to steam the buns, 1 minute more.

pull off the top bun and transfer the burgers with the onions to the bottom bun, flip, top with bun and serve with pickles and ketchup