Preheat your Blackstone griddle to 400-450°F (medium-high heat). Test temperature with a few drops of water—they should dance and evaporate within 2-3 seconds.
Divide ground chuck into 4 equal portions (4 ounces each). Gently form into loose balls without overworking the meat. Refrigerate until ready to cook.
Lightly oil the hot griddle surface. Place beef balls on griddle and let sit for 30-60 seconds to develop a light sear on the bottom.
Flip each ball so the seared side faces up. Using a burger press or two crisscrossed spatulas, press down firmly for 10-15 seconds until beef is about ¼-inch thick.
Immediately season the smashed patties generously with salt and pepper. Do not move or disturb the patties.
Cook for 2-3 minutes on the first side without touching, until edges brown and crust develops. Resist the urge to peek or adjust.
Flip burgers once. Cook second side for 60-90 seconds, then immediately add cheese slices on top of each patty.
Cover patties with a melting dome or inverted metal bowl for 30-60 seconds to melt cheese quickly without overcooking beef.
While cheese melts, butter the cut sides of burger buns and toast them face-down on the griddle for 60-90 seconds until golden brown.
Remove burgers from griddle. Assemble on toasted buns with your choice of toppings: lettuce, tomato, pickles, onions, and sauce. Serve immediately.