McDonald’s is changing up its traditional burgers and Big Macs.

The fast-food chain announced the changes will impact its classic hamburger, cheeseburger, double cheeseburger, McDouble burger and Big Mac sandwiches. The changes include softer buns that will be toasted, melted cheese instead of room-temperature, caramelized onions that will be added to the patties during grilling and, for Big Macs, more of the signature sauce.

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“We found that small changes, like tweaking our process to get hotter, meltier cheese and adjusting our grill settings for a better sear, added up to a big difference in making our burgers more flavorful than ever,” Chef Chad Schafer, Senior Director of Culinary Innovation, McDonald’s USA, said in a release.

The revamped burgers have already been introduced in Australia, Canada and Belgium and are currently available in select locations such as Los Angeles, Seattle, San Francisco, Las Vegas and Denver. All restaurants in the U.S. are expected to have the new burgers by 2024.

To market the change, the company is bringing back its infamous Hamburglar, a character made popular in the 1980s.

“Keep your eyes peeled for our very own red-handed fugitive (the OG hamburger influencer) who is back to his old burger-snatching tricks in our newest TV commercial,” McDonald’s release said “When you spot his notorious cape and striped outfit in your city, you’ll know that’s when you can head to your local McDonald’s to get your hands on our best-ever burgers.”