Slice the onions and tomatoes into long strips.

Mix all the ingredients with the beef and let it marinate for at least 3 hours.

Place it in an oven tray and cover with foil.

Leave it for about half an hour, then remove the foil and leave for another 10 minutes.

Crush the garlic clove for the tartour sauce, then mix the tahini with lemon juice. Mix well, then add a little water and salt, and mix again.

Chop the parsley and finely chop the onion, then mix them and add a pinch of sumac.