It doesn't fall from heaven, like the manna that fed the Israelites in the desert. Rather, it drips from trees, like maple syrup. Manna comes from the manna ash (Fraxinus ornus) of the Madonie mountains of Sicily; most of the small production comes from around Castelbuono.
Incisions are made during the hottest time of the year, from July to September. The sap oozes out, sometimes in meter-long lengths then bakes into long strings known as cannoli. They were a favourite of St Catherine of Siena.
Manna has medicinal uses (the locals traditionally used it as laxative). Its use as a sweetener that contains no glucose it has lately attracted some interest for diabetics. It's still fairly rare: at the moment the finest, purest cannoli cost around €150 a kilo.
Images by: web03.bruns.de, http://sicilianfoodlovers.com