Coarsely chop the walnuts. Roast in a pan without fat, remove. Peel and chop onion. Peel beetroot (put on disposable gloves - they stain strongly!) and dice coarsely. Peel, wash and dice celery and potatoes.
Heat the oil in a large pot. Sauté the onion in it until transparent. Fry beetroot, celery and potatoes briefly. Sprinkle with 1 tsp. sugar and caramelise briefly. Season with salt and pepper. Deglaze with 1 1⁄4 l water, stir in broth and bring to the boil.
Cover and cook over medium heat for about 25 minutes.
In the meantime, grate the cheese finely for the dumplings. 1⁄4 l water, butter, 1⁄2 TL salt and 1 pinch of nutmeg in a pot bring to the boil. Stir in the semolina and stir with a wooden spoon until the mixture comes off the bottom of the pot.
Remove from the heat and let it cool down a little. Then stir in the egg and cheese.