Oporto

António Cerqueira, an Australian of Portuguese descent, opened the first Oporto in North Bondi, Sydney, in 1986, under the plain name Portuguese-Style Bondi Charcoal Chicken. The name it took later came from his favourite football club, FC Porto. It began franchising in 1995 and changed hands several times through private equity, and today belongs to Craveable Brands, owned by PAG Asia Capital. It runs more than 200 restaurants in Australia and New Zealand.

The kitchen is built around chicken flame-grilled flat and basted in Portuguese-style sauces, from Lemon & Herb to the Original Chilli and the hotter Extremo Picante. The burgers take the same grilled breast fillet and put it in a bun, which makes Oporto a chicken-burger chain rather than a beef one; its best known burger, the Bondi, shares its name with the beach suburb where the chain began. The long-running slogan is “Just Gotta Go, Oporto!”.

More than 200 restaurants in Australia and New Zealand, with a branch in Dubai.

• KFC (United States, since 1952). A fried chicken empire whose best burgers are sold outside America. Also built on chicken and heat.
• Wendy's (United States, since 1969). Square burgers on round buns, because the founder refused to cut corners. Also built on chicken, heat and cheese.
• Mom's Touch (South Korea, since 1997). Korea’s chicken burger chain, famous for a whole fried thigh in a bun. Also built on chicken.
• Popeyes (United States, since 1972). The New Orleans chicken chain whose sandwich sold out America in two weeks. Also built on chicken.