Peel and wash carrots and potatoes and cut into slices or cubes. Heat 2 tablespoons of oil in a saucepan. Briefly fry the carrots and potatoes. Deglaze with 1 l water, bring to the boil, stir in broth and simmer covered for 20-25 minutes until the vegetables are soft.
In the meantime, peel and finely dice the onion for the meatballs. Knead minced meat, onion, mustard, breadcrumbs and egg yolk. Season with salt and pepper. Form approx. 20 balls from the minced meat mass with moistened hands.
Heat 2 tablespoons of oil in a frying pan. Fry the meatballs for 8-10 minutes while turning.
Wash the chives, shake dry and cut into small rolls. Mash carrots and potatoes in the soup with a potato masher until coarse. Season to taste with salt and a little nutmeg. Heat meatballs in the soup.
Sprinkle with chives.