For the meatballs, knead the minced meat, rice, grated onion, salt and pepper together well and then shape into marble-sized balls.
Transfer to a plate filled with flour. Then shake the plate back and forth so that the balls are coated with flour on each side.
Peel the potatoes and the two onions and cut into cubes. Then heat the olive oil and butter in a high saucepan and fry the onions until translucent. Then add the tomato paste and fry for half a minute. Deglaze with the water and season with salt, pepper and paprika powder. Now carefully add the meatballs and the potato cubes to the soup and cook in the soup for about 30-40 minutes over medium heat until they are cooked through. Stir every now and then.
When serving, you can sprinkle some chopped parsley over it.