Peel and chop the onion. Knead half of it with the minced meat, the spices and 0.5 teaspoons of salt to form a meat dough. Divide the meat dough into 16 roughly equal portions and shape into balls.
Heat 1 tablespoon of oil in a pan and fry the meatballs all around for 5 minutes until golden brown. Remove from pan and set aside. Rinse the mint, shake dry, then chop without the coarse stems.
Heat the broth in a saucepan and let the rice cook for about 8 minutes. Add the meatballs and simmer for another 10 minutes.
Heat the remaining oil in a pan and allow the remaining onions to become translucent. In the meantime, whisk the egg yolks with the yogurt in a bowl. Remove the rice from the stove.
Gradually add the yogurt mixture to the rice, stirring constantly. Cover the soup and let it stand for 5 minutes. Stir in the onion cubes. Serve the soup garnished with mint immediately.
A fresh cucumber salad with black olives and baguette goes well with it. If you don`t like mint, you can also use parsley or coriander instead.