Cut the buns in half, dry them in a dry, hot frying pan until a golden crust forms.
Add egg, salt, pepper and breadcrumbs to the minced meat. Mix well.
Now we are preparing our cutlets. To make them as beautiful and smooth as possible, I use a lid for a jar with a large throat. Lubricate it with vegetable oil, spread out the cling film and also lubricate it with vegetable oil. Lay out the minced meat.
Then put the cutlet without a lid on a flat surface covered with cling film. Put it in the freezer for 20 minutes. And then fry on both sides until tender.
Onions are very finely chopped and marinated in a mixture of vinegar and boiling water for 15 minutes. Then peel the onion from the liquid.
Mix mustard with ketchup in a separate bowl.
Cut the cucumber into thin slices.
Now we take our cheeseburgers.
"Cover" the rolls with a mixture of mustard and ketchup.
Sprinkle pickled onions on top.
Place on a cucumber circle.
Cover with a piece of cheese.
Place on top of the hot patty.
Put a lettuce leaf on the cutlet with the back side up. And cover the "bottom" of the bread.