Put the butter in a bowl and stir with a wooden spoon. Add half of the semolina and stir. Add the egg with the remaining semolina and stir everything again. Season with salt and nutmeg.
Put 1.5 liters of water in a saucepan and grate the beetroot into it. Then add the soup cubes and heat the whole thing. When the water boils, use a spaetzle slicer to slice the dough in. The whole thing then has to cook for 5-10 minutes.