Grate the onions: Peel and finely grate the onions, then squeeze the water out of the them.
Combine minced meat with onion, flour, egg, spices and salt: Stir the mixture up and knead it well. In order to firm up the meat and make its texture more consistent, pound it firmly against the bottom of the pan several times. Eventually, the dough should not stick to the hands and should be easily rounded.
Make round meatballs: Form round meatballs by rolling the meat between your hands. You can also fill your meatballs with chopped walnuts or dried plums. If you're making plum-stuffed meatballs, press the meat lightly to fill the gaps and create a more solid meatball.
Fry the meatballs: Pour oil in a non-stick pan and let it heat well. Gently place the meatballs inside and let them cook, without touching them for several seconds, then shake the frying pan continuously until the meatballs are browned on all sides. As soon as you realize that meatballs will not stick to the dish, you can return them with a spoon -- but don’t seal the pot yet
Prepare the tomato sauce: In a skillet, sauté chopped onion in oil, then stir in tomato paste. Cook for several seconds, then pour in water. About 4 cups of water are enough.
Put the meatballs in the sauce: When the sauce begins to boil, add the meatballs. Do so one at a time, gently placing them into the saucepan. If you add them suddenly, they could crack or break. It’s important not to close the pot lid completely and leave it half open. It takes about 50 minutes for the meatballs to be well-cooked. The size of the meatballs also affects baking time: smaller ones cook faster.
Steam rice in a separate pot. I have covered the subject of rice in another recipe entitled “Persian Rice with Bread tahdig.” Serve the meatballs with rice or bread. And don't forget the fresh veggies!