Cut the onions in half and then into thin strips
Transfer the onion strips to a large bowl and loosen them with your hands
Add ice cold water with some ice to completely cover the onions and let them soak for at least 3 hours
Drain the onions and transfer them back to the large bowl
Add the salt, black pepper, oregano, parsley, chives, and olive oil, and mix everything well
Add the lemon zest and juice, and mix again
Transfer the onions to jars and pour the remaining liquid from the bowl over them, dividing it evenly
