Boil the chicken in salted water. Debone the meat and shred it into coarse pieces.
In a separate pot, heat the oil. Add the flour and fry lightly. Remove it from the heat and add the hot broth from the boiled chicken.
Mix until you get a homogeneous mixture. Put it back on the stove and let it boil 5-6 minutes. Once ready, slowly and carefully add the yolks and yoghurt, whipped in advance.