By DAVID ARNOLD

After several weeks of wandering the desert, the Israelites fleeing Egypt were hungry. So God conjured up two things for them to eat, the Bible says. In the evening, there were quails. “In the morning,” the Book of Exodus says, “there was a layer of dew around the camp. When the layer of dew evaporated, behold, on the surface of the wilderness there was a fine flake-like thing, fine as frost on the ground.

When the sons of Israel saw it, they said to one another, ‘What is it?’ ” In ancient Hebrew, “what is it” can be rendered man-hu, a likely derivation of what this food has come to be called, manna. The Bible describes it as being “like coriander seed,” and “white, and its taste was like wafers with honey.” But as miraculous as its biblical apparition may seem, manna is real and some chefs have been cooking with it.

As in the Bible,
mannas appear as if
by providence.

The dozens of varieties of what are called mannas have two things in common. They are sweet and, as in the Bible, they appear as if delivered by providence, without cultivation. Most of this manna is either dried plant sap extruded from tiny holes chewed out by almost invisible bugs, or a honeydew excreted by bugs that eat the sap.

Rarer are the mannas not from sap, including Trehala manna, the sweettasting cocoon of the Larinus maculates beetle from Turkey; and mannalichen (Lecanora esculenta), which occasionally dries up and blows around to form semisweet clouds out of which manna settles into drifts from western Greece to the central Asian steppe.

Mannas form best in extremely dry climates ? like the Middle East’s ? where sap oozes at night and dries up in the morning. The favored theory on what the Israelites called manna is the sap of a tamarisk tree. In Calabria and Sicily, Italian farmers cut the bark of the flowering ash (Fraxinus ornus) to get the dried sap, the only domesticated form of manna.

Behroush Sharifi, a New York dealer in rare spices and dried foods from the ancient Silk Road who’s known as the Saffron King, imports two venerable forms of manna from Iran: Hedysarum manna and Shir-Khesht manna.

Both look like what they are: stuff knocked off bushes by the desert gatherers who harvest it. They contain bits of twigs and leaves and who knows what else. The Hedysarum is $22 an ounce, and the Shir-Khesht is $28. (Information is available by writing to info@saffronking.com; Mr. Sharifi plans to open an online store this summer.)

Garrett McMahon, a sous-chef at Perilla in Manhattan, uses Hedysarum manna to finish off a foie gras terrine with Marcona almonds, candied kumquats and toasted brioche. Hedysarum manna comes from Hedysarum alhagi, the camel thorn bush and tastes like a combination of maple syrup, brown sugar, blackstrap molasses, honey and nuts.

Paul Liebrandt of Corton in Manhattan used Shir-Khesht manna in a dish of charred Frog Hollow Farm apricots, fresh wasabi and Kindai kampachi. “No two people taste manna the same way” he said. “I might taste a haunting minty-ness, while you might detect a whiff of lemon. No other ingredient is like that.”