How Burger King Cooks Dozens Of Flame-Broiled Patties At Once

Burger King is one of America's oldest still-operating chain restaurants, and its trademark flame-grilled burgers are a big reason why. Even as the signature Whopper got its first refresh in a decade in February 2026, with an enhanced bun for improved taste and more creamy mayonnaise, BK didn't touch the beef patties and their charred grill flavor. But as much as fast food is designed to irresistibly ping our taste buds, it also has to live up to its name and be quick. The chain's cooking equipment keeps things moving by being able to turn out many patties at the same time.

Burger King uses large upright broilers with a conveyor belt system that moves the beef patties through actual flames, so they're technically flame-broiled instead of grilled (though the process mimics the results of open-flame grilling) to achieve their flavor. Made for BK by two companies, Duke Manufacturing and Nieco, the enclosed machines also hold in heat, which surrounds the meat and contributes to faster, more consistent cooking. There is pre-programmed timing for each product that is selected before cooking, with the whole process taking around two to four minutes.

The equipment is designed to make the burgers in batches instead of individually, increasing the number that can be produced all at once and also contributing to consistent results. Duke's machines, for example, can cook groups of 12 burgers or eight Whoppers in just four minutes. Frozen patties are arranged in a couple of rows on a loading tray, and then pushed into the broiler, where they will all be done at the same time. Additionally, the tray can be refilled while the batch cooks, saving time so it's ready to go in next.

All Burger King patties — including the Whopper and Whopper Jr., the Impossible Burger, and limited-time specials — are prepared using its signature flame-broiled process. The same broilers are used for all patties, with no separate equipment for plant-based options (though the chain officially offers a non-broiler version upon request).

The chain has made other products, including poultry, in the broilers for different menu items in the past, and likely will again. The BK Broiler chicken sandwich it sold from 1990 to 2002 was flame-broiled, and one Redditor who worked there remembered having a special separator to keep the poultry on one side and the burgers on the other while cooking "to prevent flavor contamination." The Chicken Whopper, made the same way, followed soon after.

Some items introduced for limited-time testing in just a few locations have also been cooked in the broilers, like a new chicken sandwich and chicken wraps in 2024. There were also Grill'wich breakfast sandwiches tested in 2023, made using the same type of Croissan'wich fillings, but with flame-broiled flatbread buns.