That was the dietry advice in tenth century Egypt. And being the tenth century, not following that advice didn't result in Gillian McKeith going through your poo. It resulted in flogging and public shaming.
Egypt at the time was ruled by eccentric (polite for barking mad) Al-Hakim bi-Amr Allah the sixth Fatimid caliph. He issued a number of arbitrary laws that were getting weirder and more eccentric as years goes by.He tried to prevent women from going out so he banned shoemakers from making women shoes. Christian were only allowed to ride horses if the saddles were wooden and undecorated. He banned fishermen from catching any fish that had no scales and forbade people from selling or eating such fish. And to our subject, he banned watercress, rocket and most importantly Mulukhiyah the national and favourite dish of Egypt. Egyptians loved Mulukhiyah since the dawn of time. It was even mentioned in Pharaohs texts.
Nobody really knows why he banned Mulukhiyah. Some people claim that it was the favourite dish of Mu'awya ibn Abi Sufyan the archenemy and hate figure of Shiaa Muslims. Some say greens are sheep and cattle food and eating them will bring human intelligence to the level of livestock. Some theory goes that Mulukhiyah is a strong aphrodisiac and by banning it he was trying to cut promiscuity. We in Damascus have a theory/urban legend to explain it. Although the theory is funny, it is offensive and un-PC so I will leave it out.
Mulukhiyah (Mlukhyeh as we Syrians pronounce it, Jute Mallow or Jew's Mallow in English) is a green leaf vegetable with a distinct bitter taste. To me, it has the most distinct and unusual flavour compared to any other Middle Eastern ingredient. It has a natural thickening agent that could turn unpleasantly slimy if not cooked properly. In Syria we never break the leaves or leave any stalks to avoid that.
Mulukhiyah with rabbit is Egypt top dish. Mulukhiyah leaves are very finally chopped and cooked is soup-like stew. In Syria and the rest of the Levant it is a firm favourite. We cook it with chicken and the leaves used whole. The leaves are used fresh or they can be dried or frozen to be used out of season.
In London it is almost impossible to find Mulukhiyah fresh. You can get the dry leaves from Middle Eastern supermarkets. I get mine from Damas Gate in Shepherd's Bush. Don't even touch the frozen variety as you will end up with a big lump of slime.
Here is my recipe for Mulukhiyeh Syrian style:
Dry Mulukhiyah 100g packet
Chicken breast on the bone (bones for added flavour to the stock if available)
Garlic 8 cloves
Coriander chopped 1 table spoon
Chicken Stock 1 cube
Small onion or two shallots
Salt and pepper
Soak Mulukhiyah leaves in plenty of cold water for two hours.
Cover the chicken breast with water and bring to boil skimming the water to get clear stock. When water reach boiling point reduce heat to simmer and add coarsely chopped onion and the stock cube. Cook till the chicken is fully cooked then remove from stock.
Drain the mulukhiyah leaves and wash them. That will get rid of the slime. Add the leaves to the stock and cook. Peel and half five garlic cloves and add them to the pot. Remove the chicken meat, shred it and add it to the pot. Continue cooking till the mulukhiya is cooked. It should take 20 - 30 min and will keep some bite. There is no right and wrong to the amount of stock in the finished dish. I like mine fairly dry. Crush the rest of the garlic and add with the coriander and cook for a final 3 minutes.
Serve with a sprinkle of dry chilli and squeeze of lemon. You can serve it hot with Vermicelli rice or room temperature with Arabic bread.