01 -
Slice onions extremely thin using sharp knife or mandolin, aiming for uniform thickness for even cooking.
02 -
Divide ground beef into exactly four equal 4-ounce portions and gently form into loose balls.
03 -
Heat large cast iron skillet or griddle over medium-high heat until very hot, about 2 minutes.
04 -
Add canola oil to heated surface, ensuring even coating across cooking area.
05 -
Place beef balls onto hot surface and immediately press firmly with spatula to create very thin patties.
06 -
Season flattened patties with salt, pepper, and garlic powder mixture immediately after smashing.
07 -
Top each patty generously with about 1/2 cup sliced onions, allowing some to fall onto cooking surface.
08 -
Cook undisturbed for approximately 2 minutes until meat develops dark brown crust.
09 -
Flip patties carefully, scraping up any crispy bits and incorporating back onto burgers.
10 -
Place buns face-down on top of patties to steam for about one minute.
11 -
Remove steamed buns and place cheese slices on patties while finishing cooking.
12 -
Transfer patties to buns once cheese melts and meat reaches desired doneness.
13 -
Scrape any remaining caramelized onions onto burgers before serving.
14 -
Serve immediately while patties are hot and cheese is melted.
15 -
Optional: add condiments of choice, though traditionally served plain to highlight onion flavor.