# Ingredient List:
→ Beef
01 - 1 lb ground beef (80/20 blend)
02 - 1/2 teaspoon kosher salt
03 - 1/2 teaspoon freshly ground black pepper
→ Onions
04 - 2 large yellow onions, thinly sliced
05 - 2 tablespoons unsalted butter
06 - 1 tablespoon olive oil
07 - 1/2 teaspoon sugar
08 - Pinch of salt
→ Cheese & Buns
09 - 8 slices American cheese or cheddar
10 - 8 slider buns (mini brioche or potato rolls)
→ Toppings & Condiments
11 - 2 tablespoons mayonnaise
12 - 2 teaspoons yellow mustard
13 - 8 dill pickle slices (optional)
# Steps:
01 - In a large skillet over medium heat, melt butter with olive oil. Add sliced onions, sugar, and a pinch of salt. Cook, stirring frequently, until onions are soft and golden brown, approximately 20 to 25 minutes. Transfer to a bowl and set aside.
02 - In a small bowl, combine mayonnaise and mustard. Mix well and set aside.
03 - Divide ground beef into 8 equal portions of approximately 2 ounces each. Shape into balls without overworking the meat.
04 - Place a large cast-iron skillet or griddle over medium-high heat until very hot, approximately 2 to 3 minutes.
05 - Place beef balls in the hot skillet with space between each. Immediately smash each ball flat with a sturdy metal spatula. Sprinkle with salt and pepper. Cook for 1 to 2 minutes until edges are crispy and browned.
06 - Flip patties, top each with a slice of cheese, and cook for 1 additional minute until cheese is fully melted and burgers are cooked through.
07 - Split buns and toast them cut-side down in a dry skillet or under a broiler until golden brown.
08 - Spread slider sauce on the bottom buns. Layer each with a patty topped with melted cheese, a generous spoonful of caramelized onions, and a pickle slice if desired. Crown with the bun lids. Serve immediately.