Start by forming four 4 oz patties with a wall around them.
Make four more slightly smaller 4 oz patties.
On the patties with the walls, place one slice of American Cheese folded in fours on top of them.
Place the non-walled patties onto the others and begin to pinch and roll the edges together forming one burger patty.
Salt and pepper the top of the patty with coarse kosher salt and fresh ground black pepper.
Preheat a cast iron skillet over medium-high heat.
Place your four burger patties in the skillet and cook on each side for about 10 minutes.
Remove the burgers and reduce the heat to medium.
Add some butter and onions stirring to coat the onions in the beef lard and butter. Sprinkle with a little salt bring the moisture out.
Allow the onions to cook for about 10 minutes but not caramelize. Pour these into a fine strainer and set aside as a garnish.
Assemble burgers and Serve.
ENJOY!