Make the burger patty: Add the following ingredients to the mixing bowl: minced beef, egg, bread crumb, ginger and garlic paste, salt, and pepper. Thoroughly mix the ingredients and make small balls of patties. One ball of patty can be a hundred grams for one burger, or two balls can be fifty grams each for one burger.
Cook the onion and the patties: Preheat the frying pan on medium-low heat, add cooking oil, and sauté the onion and the leek for two minutes, then remove them from the pan. Then, add extra oil and add the ball of patty to the pan. Place the parchment paper on top of the patty and press down on it with the burger smasher in a circular motion until the patty is flattened to one centimetre.
Flip the burger patty: Flip the patty and cook for another two minutes. Add more cooking oil if necessary. Avoid over-pressing down on the patty so that the juicy, flavoured fat is retained. Add the cheese on top of the patties when cooked, and turn off the heat for the pan. Remove the patty after fifteen seconds.
Add the fillings: Toast the buttered buns and layer the burger. First, layer the lettuce, then sautéed onion and leek, the smashed burger patty, sliced cucumbers and tomatoes, mayonnaise, and finally, complete the burger with the top bun. Serve with your favourite drink and the sides like French fries.