1 small onion, coarsely grated
1½ pounds 100% grass-fed ground beef
1¼teaspoon kosher salt, plus more
½teaspoon freshly ground black pepper, plus more
1tablespoon vegetable oil
Hamburger buns and desired toppings (for serving)
Using your hands, gently mix onion, beef, 1¼ tsp. salt, and ½ tsp. pepper in a medium bowl. Gently shape into four 1½”-thick patties (loosely formed patties will be more succulent).
Heat oil in a large skillet, preferably cast iron, over medium-high heat. Season patties with salt and pepper, place in skillet, and immediately reduce heat to medium. Cook 4–6 minutes per side for medium-rare. Serve on buns with desired toppings.
Patties can be formed 4 hours ahead. Cover and chill.