How Long to Cook Grilled Smash Burgers (Cast-Iron Griddle Insert on Grate) in the grill
Specification: 2 oz balls of 80/20 chuck (roughly ping-pong sized, 8 balls from 1 lb), formed loosely and kept fridge-cold; grill fitted with a preheated cast-iron griddle or 12-inch skillet centred over the hottest burner
3-Step Execution Protocol
Preheat grill to Cast-iron surface at 500–550°F (260–288°C), preheated 10 minutes with grill lid down before smashing. Clean and oil grates. Prepare grilled smash burgers (cast-iron griddle insert on grate) (2 oz balls of 80/20 chuck (roughly ping-pong sized, 8 balls from 1 lb), formed loosely and kept fridge-cold; grill fitted with a preheated cast-iron griddle or 12-inch skillet centred over the hottest burner).
Cook for 3–4 mins total per burger (60–90 sec smashed side, single flip, 45–60 sec second side plus cheese melt with lid down). Flip at the 2-minute mark for even browning.
The smashed side has a lacy dark-mahogany crust with irregular crispy edges that extend past the patty's footprint, and pressing the centre gently springs back with no jiggle. Confirm internal temperature reaches 160°F internal (USDA FSIS safe minimum for all ground beef) — reached quickly because a smashed patty is only 1/4 inch thick. Rest for 0 minutes before serving.
USDA FSIS 160°F safe minimum for all ground beef; 500–550°F griddle temperature and single-smash timing from J. Kenji López-Alt's smash-burger testing (Serious Eats) and Meathead Goldwyn's smash-burger technique piece on AmazingRibs.com. Cast-iron-on-grate method used to translate the flat-top standard to a home grill, as documented in Weber's Way to Grill Every Meal (Jamie Purviance) grill-griddle chapter.