Combine all the ingredients in a bowl and mix well. Divide into 4 equal portions.
Shape each portion into a patty.
Coat the patty with bread crumbs.
Heat oil in a kadhai and deep-fry the patties till they are golden brown.
Drain on absorbent paper and keep aside.
How to proceed
Slit each burger bun into 2 halves. Toast both sides of each slit bun lightly on a tava (griddle).
Place one patty on the base of a toasted burger bun. Top with 1 tbsp of mayonnaise, some tomato slices, onion slices, shredded lettuce and sprinkle salt and pepper. Sandwich with the other half of the burger bun.
Repeat with the remaining ingredients to make 3 more burgers.