"This burger is the kind you’d get if you hit a twenty four hour diner early enough that the last orders from breakfast are still leaving the flat top (or if you hit it late enough at night that the early birds are already eating breakfast). The flat tops at places like this are invariably kept at a cooler temperature than those at dedicated burger joints that aim to sear and serve as fast as possible. This means that a thicker burger patty has plenty of time to pick up flavor from the clarified butter used to fry the hash browns and eggs and the bacon grease that coats the griddle as the outside slowly browns and the center reaches a perfect medium are.
A slice of gooey American cheese (or some sharp cheddar if you’re feeling fancier), some onions (sliced pole- to- pole to maximize onion flavor while minimizing pungency), some slices of dill pickle, and a smear of mayo are all this burger needs to achieve beefy nirvana, but you can top it up any way you choose.
Note: When shopping for ground beef, look for a fat content of at least 20 percent (80/ 20 beef). Plain old ground chuck will do. For a superior burger, combine 50 percent ground sirloin with 25 percent ground fatty short rib and 25 percent ground brisket. To clarify butter, place it in a small microwave safe container and microwave in 15- second increments until fully melted. Skim off the white scum from the top surface with a spoon and discard. Carefully pour off and reserve the yellow butterfat, discarding the milky white liquid at the bottom. The yellow butterfat is your clarified butter."
Form the beef into two 6-ounce patties about 5 inches wide and 3/4 inch thick (it should be about 1 inch wider than your bun). Season heavily on all sides with salt and pepper.
Heat the bacon strips in a large cast-iron skillet and cook over medium heat, turning occasionally, until crispy on all sides. Transfer to a paper towel–lined plate. Use a spoon to carefully remove any large bits of debris left in the pan from the bacon.
Add the clarified butter to the skillet and increase the heat to medium high. Add the hamburger patties and cook without disturbing until a deep crust develops on the first side, about 1 1/2 minutes. Lower the heat as necessary if the fat starts to smoke excessively. We’re aiming for slow and steady browning over a hard dark char here.
Flip the burgers, top with cheese, and continue to cook until the second side is browned and the center of the patty registers 125°F on an instant read thermometer for medium rare or 130°F for medium. Transfer the burgers to a plate and set aside to rest. Scrape the skillet out into the sink, removing any gunk but leaving a thin sheen of oil in the bottom.
Toast the buns in the now empty skillet, turning them gently for even browning.
Construct your burgers, topping as desired, and serve immediately.