Wash the endive well and cut into strips that are not too narrow. Boil the eggs hard and then dice them. Peel and dice the jacket potatoes. Dice the onion and mix everything. Make a creamy salad dressing from cream, quark, yoghurt, mustard, salt and pepper, stir with milk if necessary and pour over the salad. Mix and eat right away. We like a gourmet fillet with it.