A Smash burger is exactly what you think it is; balls of ground beef smashed onto a hot griddle. You'll want to smash them pretty thin so they cook quickly, but it also gets you those crispy, browned edges while still keeping the interior nice and juicy. Now is not the time to cut calories or skimp on salt: Go for ground chuck that is at least 80/20. If you can find a blend with ground brisket or short rib, all the better. The best burger comes with being liberal with kosher salt—it is beef's best friend. —James Schend, Pleasant Prairie, Wisconsin
Optional: Mayonnaise, sliced American cheese, sliced tomato, dill pickle slices, lettuce, ketchup and yellow mustard
Place a 9-in. cast-iron skillet over medium heat. Meanwhile, gently shape beef into 4 balls, shaping just enough to keep together (do not compact).
Increase burner temperature to medium-high; add oil. Add 2 beef balls. With a heavy metal spatula, flatten each to 1/4- to 1/2-in. thickness; sprinkle each with 1/8 tsp. salt and 1/8 tsp. pepper. Cook until edges start to brown, about 1-1/2 minutes. Turn burgers and sprinkle each with additional 1/8 tsp. salt and 1/8 tsp. pepper. Cook until well browned and a thermometer reads at least 160°, about 1 minute. Repeat with remaining beef.
Serve burgers on buns with toppings as desired.
Test Kitchen tips
Want a Smash Cheeseburger? Add a slice of your favorite cheese right after you flip it.
The more you work the ground beef the tougher the burger will be. So use just your fingertips to form the loose balls. Don't worry about tucking in all those loose strands that may stick out; they turn into well-browned bits of goodness.
There is a lot of flavor in the browning, so after you smash them don't move them until you're ready to flip. If you have the space, flip the burger onto an unused area of the skillet; it's much hotter than the section of pan where the burger was.
Using a meat mallet to press on the spatula while you're flattening the burgers will help to form them evenly and will help keep your spatula from bending.