Peel and finely chop the onion. Knead onion, minced onion, quark and breadcrumbs. Season with salt, pepper and dried herbs. Form into 2 flat steaks. Heat oil and fry the teaks for about 10 minutes, turning them over.
In the meantime wash, clean and slice the tomato. Wash the lettuce leaves. Cover the slice of bread with lettuce, tomato slices and minced steaks. Melt butter in the frying fat. Add egg and fry briefly.
Also arrange and serve garnished with thyme. Sour cream with roasted onions tastes great with it.