1Cut the beef into cubes and place in 2l of cold water.
2Fry the onion without fat in a deep pan until golden brown.
3Wash the bones in cold water and put all together with the veg into the pan.
4Bring to the boil and let simmer for about 2 hours.
5Let the soup cool and remove the fat.
6Whisk the egg whites with 250 ml of cold water, and stir slowly into the soup.
7Simmer until it becomes transparent.
8Drain through a dish towel so the broth is clean.
9Add salt to taste and sprinkle with chive or parsley.