Gaz (candy)

Gaz () is an Iranian nougat originated in Isfahan. It is widely known as Persian Nougat in American and European countries.
Etymology.
The Persian word "Gaz" is associated with "gaz-angebin" which translates to 'Honey of Gaz', in reference to a species of Tamarisk, "T. gallica" that is native to the Zagros mountain range located to the west of Isfahan. Gaz is traditionally presumed to be the sap of the Tamarisk tree.
History.
Gaz dates backs to 450 years ago in Isfahan, when the sap found on the Tamarisk tree was combined with flour, bread, pistachios, almonds and chocolate in traditional and industrial workshops. The height of this mountain tree reaches a height of two meters and it usually grows in good weather in the mountains of Bakhtiari and Khansar. The product of this tree becomes ready to harvest in the late summer and the shiny and yellow grains come out in the stems like millet. At this time, the owners of the trees must harvest them before the autumnal rains.
The sweet, milky honey (angebin) found on the Gaz plant is associated with "manna", a food mentioned in the religious texts of the Abrahamic religions. 
Manufacture and style.
Although originally believed to be sap manufactured by the Tamarisk tree, the sticky white substance was found to be formed from honeydew, which is exuded from the anus of the nymph of a psyllid insect, either "Cyamophila astragalicola" or "C. dicora", in its final instar, which live on plants of "Astragalus adscendens", and is collected annually and is combined with other ingredients including pistachio or almond kernels, rosewater and egg white. Modern versions of gaz may not contain gaz of Khansar and may use sugar and corn syrup as substitutes for psyllid manna.
The traditional way to serve gaz is in round pieces that are about 2 inches in diameter and up to 1/2-inch thick. A modern presentation is to serve the nougat cut into smaller rectangles. Depending on the ingredients mixed in, gaz can have a subtle rose flavor, a nutty taste, or a savory and pungent profile. It can be white, or it can become another color because of the addition of spices (such as saffron) or nuts.
Nowruz.
Celebrations such as Nowruz, the Persian New Year, feature gaz. During the Nowruz holiday, family and friends visit each other's homes and, typically, the host offers fruits and sweets to their guests. Served with sherbet or tea, gaz is a favorite delicacy and a much-appreciated gift as it helps to ensure that a household will have ample snacks to serve all holiday visitors.