Divide the ground beef into 12 two-ounce patties. Flatten each patty out to fit the size of your slider buns. Season each side with salt and pepper. Heat a cast iron or stainless steel skillet over high heat and cook the patties until nicely browned on each side and cooked to your desired doneness. Using a pastry brush, brush each patty with teriyaki sauce, then top with two small squares of cheese and brush with additional sauce. Melt the cheese, then transfer the patties to the prepared slider bun bottoms. Top with pineapple and lettuce and add the bun tops.