Fiber of mature molokhiya plants is known as Jute, but for use as food the plant is picked young and cooked as greens. While thought native to India, it has been the most important green in Egyptian cooking since ancient times. Consequently, it's available frozen in stores serving Near Eastern communities In season (Summer months), it's available fresh in Southern California, sold as "Okra Leaf". In Egypt leaves are also dried (they are thin and dry quickly) and are crumbled into a powder for use in teas and soups.
The leaves are quite mucilaginous when cooked. Most Americans would consider them "slimy", but in North Africa and the Levant the effect is much liked. In these regions the most common use is in Chicken stews, particularly with rice.
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Buying: Fresh molokhia is usually sold as "Okra Leaf" which it is not. Okra leaves are broad with a fingered shape. It is now quite common here in Southern California in markets that serve a Near Eastern, Indian or Philippine community. The leaves are thin and wilt very quickly so buy them last and get them home and into the fridge immediately to keep them from getting dried edges.
If they have become wilted you can refresh them by cutting the stem ends as for cut flowers, then float the entire fronds in cold water for an hour or so. Just sticking the cut ends in water does no good at all.
Prep: To use, pick off the leaves and wash them. If you will be storing them for a while give them a good spin in your salad spinner, then wrap loosely and refrigerate. You can also use the tender ends of thick stalks (thin ones are fibrous). Bite into the left-over end and if it's fibrous you cut too far down.
Freezing: Prep leaves as above. Bring plenty of water to a full boil in a fairly large pot over highest heat. Pour in the leaves and keep them submerged by poking down with a wooden spoon. As soon as the water is back to a boil, measure 1-1/2 minutes. Drain. Bag with water to prevent freezer burn.
Cooking: Molokhia is most often chopped small or rolled and shaved into threads to bring out its mucilaginous qualities which are much desired in Near Eastern cooking. It is then added to soups a few minutes before serving. Whole leaves are use in Borani recipes.
Frozen molokhia is almost always already chopped fine. It is generally added to soup while still frozen and stirred a little until completely thawed and the soup is back to a simmer.