In a mixing bowl, combine 500 grams of minced chicken or mutton, 1 finely chopped onion, 1/2 cup breadcrumbs, 1/4 cup chopped coriander leaves, 1 teaspoon ginger-garlic paste, 1 teaspoon garam masala, 1/2 teaspoon red chili powder, salt to taste, and mix well.
Divide the mixture into equal portions and shape them into burger patties.
Preheat a grill or tawa on medium heat. Apply some oil on the patties and cook them for 4-5 minutes on each side or until they are cooked through and have a nice char on the outside.
In a small bowl, mix 1/4 cup of barbecue sauce with 1 tablespoon of mayonnaise.
Slice burger buns in half and toast them on the grill or tawa for a minute.
Assemble the burger by spreading the barbecue-mayonnaise sauce on the bottom half of the bun, placing a lettuce leaf, followed by the cooked patty, a slice of tomato, a slice of onion, and finally the top half of the bun.