Preheat your flat-top grill and grease it with 1 tablespoon vegetable oil. In a small bowl, stir together 1/2 teaspoon salt, 1/2 teaspoon black pepper, 1/2 teaspoon garlic powder, and 1/2 teaspoon onion powder. Set aside.
Have the burger buns, cheese, and toppings ready before the beef hits the pan. Smash burgers move fast.
Divide 24 ounces 80/20 ground beef into 3-ounce portions and roll them into balls. You should have 8 balls total. Season the balls of meat with some of the seasoning mixture on the top.
Place the burger balls, seasoning side down, onto the grill. Using a piece of parchment paper and a cast-iron weight, smash each ball down as thin as you can, really concentrating on the edges. Season the top after smashing.
Allow to cook until the meat looks lacy and browns around the edges, about 2 minutes. Using a large griddle spatula, scrape under the patty and flip it over. Immediately grab the 8 slices American cheese and place one slice on top of each burger. Continue to cook until the cheese melts, about 2 minutes.
For doubles, stack one patty on top of each other until you have 4 burgers. Transfer each burger to a burger bun and add your favorite toppings. Serve immediately.
Notes
Nutritional information includes a burger bun, no toppings.
We end up using almost all of the seasoning mixture, but season to your taste.