Chop the onion finely braise it in a little oil until softened. Add the tomato paste, diluted with 1 tbsp water, and the paprika. Leave it on the heat until the water evaporates, then remove.
Knead the mince well and shape meatballs, roll them in flour and drop them in boiling salted water 1 by 1, with the bay leaf. Boil the meatballs as is for about 20 min. on low heat.
Make the sauce by braising the flour in 3 tbsp oil until it changes color slightly. Pour part of the broth from the meatballs over it while stirring nonstop.
Pour in the beaten yoghurt in a thin trickle and leave it on low heat to boil for 10 min., while stirring periodically.
Beat the eggs in a bowl and begin to add ladles of the sauce to them, while stirring energetically nonstop.
Put the meatballs in a large serving plate and pour the sauce (strained beforehand) over them. Sprinkle with finely chopped parsley.