Heat the oil in a pan and sweat onions until they get golden.
Add the beef. Turn it around and then add the spices, turmeric, salt and pepper.
When the beef is browned add the tomato paste, mix to combine, bring mixture to a boil and then simmer on low for 30 minutes.
Pour oil in a pot and put potato or bread for Tahdig. If you use potato, fry one side and then turn over.
Put one layer of boiled spaghetti following a layer of the sauce, mix to combine and continue layer by layer until it's finished.
Use a medium heat for 10 minutes or until it starts steaming, then lower the heat and let it steam for 45 minutes.