pistachios are the culinary nut of a tree, which originated in persia, but can now be found throughout the middle east and the mediterranean area, as well as the united states. most commonly they are probably consumed salted and roasted. but they have a particularly wide function in pastries where they are commonly ground to a paste the combined with chocolate to form pistachio cremini feelings or with a custard base then frozen and churned to produce pistachio ice cream of course. on the savoury side, they find there way into cheeses particularly pecorino, or of course into mortadella from bologna. Or as was done here previously as a pistachio pesto.
in italy pistachios are famously produced on the island of sicily, from the area of bronte on the slopes of the volcanoe mt. etna. they are notably greener in color and particularly flavourful.