Grate the potatoes and squeeze to get rid of their water. Add in a Large bowl.
Grate the onions and pass through a sieve to get rid of the excess water. Put in the bowl with the grated potatoes.
Add the meat in the same bowl and add the parsley, 1 tablespoon of mint, eggs, 2 teaspoons of salt & 1 teaspoon of pepper. Mix well to combine, cover with plastic wrap membrane and let rest in the fridge for 1-3 hours.
In the meantime, add the yoghurt in a medium size bowl along with the olive oil, 2 tablespoons of mint, 1 teaspoon of salt, ½ teaspoon of pepper and the ouzo. Fold and mix well. Keep aside refrigerated.
Take the minced meat mixture out of the fridge and form into golf size balls.
Place a large and deep saucepan into medium-high fire and fill upto 2 cm with the oil. When hot, if you have a thermometer try to reach 190 degrees C, cook the meatballs in batches, carefully adding them one by one without overcrowding the pan and cook until nicely browned, 2-3 minutes per side. With a slotted spoon turn them on the other side and cook the same way. Take out on a flat dish lined with paper towels to absorb the excess oil. Repeat for the rest of the meatballs.
Serve with the yoghurt sauce along with French fries.