01 - Heat a grill pan or skillet over medium-high heat until hot.
02 - In a mixing bowl, combine ground beef with salt, black pepper, garlic powder, and onion powder. Mix gently to combine without overworking the meat.
03 - Divide the beef mixture into 8 equal portions and form each into small patties approximately 2 inches (5 cm) in diameter.
04 - Place patties on the preheated pan and cook for 2 to 3 minutes on each side until browned and cooked to preferred doneness.
05 - During the last minute of cooking, top each patty with a slice of cheese to allow melting.
06 - Slice slider buns and brush cut sides with melted butter. Toast them butter-side down in a pan or under a broiler until golden brown.
07 - Spread mustard on the bottom bun if desired. Layer lettuce, a cheese-topped patty, two pickle slices, and ketchup if using. Cover with the top bun half.
08 - Serve sliders immediately while hot for optimal flavor.