Clean and wash the kohlrabi and precook in plenty of boiling salted water for 20-25 minutes. Peel and wash the carrots and cut them into small cubes. Peel and chop the onion. Heat the fat in a pot and fry the onions in it until transparent.
Add carrots and braise briefly. Deglaze with stock, bring to the boil and add the polenta semolina while stirring. Let simmer for about 5 minutes, then let it swell for 5-10 minutes on the switched off plate.
Fold in the cheese, up to 2 tablespoons, and season the polenta with salt, pepper, nutmeg and curry. Rinse kohlrabi cold and hollow out with a ball cutter or teaspoon. Spread the polenta into the kohlrabi, sprinkle with the remaining cheese.
Put it in a mold. Chop hollowed pieces of kohlrabi and distribute them in the form. Mix cream with salt and pepper. Wash the chives and, except for a little bit for garnishing, cut into fine rolls.
Put back one tablespoon of rolls. Add the rest to the cream and pour over the kohlrabi pieces. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for 25-30 minutes. If necessary, add sauce thickener shortly before the end of the cooking time and heat up for 5-10 minutes.
Sprinkle with remaining chives and garnish.