Mix the minced meat with the egg, 1 tablespoon of mustard, salt and pepper and form 4 burger patties out of it. The patties should be a bit larger than the buns.
Peel the potatoes and cut into french fries. Fry at 150 degrees until a light crust has formed on the outside. But they shouldn`t have any color yet. Drain the french fries on paper towels.
Cut the rolls open and cover the underside with a slice of cheese. Place in the oven at 180 degrees until they are lightly crispy.
Meanwhile, cut the onions into rings and the tomatoes into slices. Fry the patties, fry the bacon and sauté the onions until translucent.
Fry the french fries a second time until they are golden and then season with salt.
Top the burgers with the meat, lettuce, bacon, tomatoes, onions and hamburger sauce or ketchup, mustard and French fries sauce.