It's just called tahin in Italian. The jar I have in my fridge is Sunita brand and imported from Greece. I got it at my local health food shop. I've also seen it at middle eastern grocery stores and at Piazza Vittorio markets here in Rome.
I'm sure you'll be able to find it in a city as big as Venice or at least in Mestre where (I assume) there are more immigrants.
When my daughter was here visiting from Costa Rica over New Years, she saw tahini in the NaturaSi store in Siena and at the Esselunga in Arezzo.
Ciao, Ben
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Posts: 291 | Location (City & State): Monte San Savino (AR) | Registered: 02 February 2005