Cut the buns in half and roast in the oven.
Cut tomatoes and gherkins into thin slices, onion into thin rings.
Fry the slices of liver cheese in oil for c. 10 minutes until brown. Crack the eggs into a frying pan, let them set and fry the fried eggs from the second side as well. Season with salt and pepper.
Spread mustard on the cut surfaces of the buns and arrange lettuce leaves on top. Put 1 slice of liver cheese, 1 fried egg, tomatoes, gherkins and onion rings on each base. Place the lid on top and secure with wooden sticks.