01 -
In a mixing bowl, combine lean ground beef, finely chopped onion, kosher salt, and black pepper. Mix gently to incorporate ingredients without overworking.
02 -
Shape the beef mixture into 12 equal small patties, sized to fit the slider buns. Heat a non-stick skillet over medium heat and cook patties 3-4 minutes per side until browned and cooked through. Drain excess fat carefully from the pan.
03 -
Split slider buns horizontally. Place a bottom bun half on a baking sheet, add half a slice of cheddar, top with a beef patty, then cover with another half slice of cheddar. Finish with the corresponding top bun half.
04 -
Brush melted butter evenly over the tops of the slider buns and sprinkle sesame seeds immediately to ensure adhesion.
05 -
Preheat oven to 175°C (350°F). Bake assembled sliders uncovered for 10-12 minutes until cheese is melted and buns are lightly toasted without becoming soggy.
06 -
Remove sliders from oven and serve warm. Ideal accompaniments include dill pickles and baked potato wedges.