What I've always found interesting aside from the heavy deep fried food that I love is that they don't charge you up front. Even in crowded Venice, when you are done eating you just tell the guy what you ate and drank and pay.
Here is the approximate location: On the East side of the Rialto Bridge there is a little plaza, Campo San Bartolomia, from there walk a little more east near the end of the plaza turn left (north) on a little alley when you see the sign in the picture attached. We think the name of the street it's on is Calle della Bissa. Will have to check the names next time we are there. If you are coming from the train station just follow the Strada Nuova all the way around tell you get to the plaza. Or just follow signs to Rialto from wherever you are.