Passata roughly means “haven been passed (through)” – and in the case of tomatoes, it means having been passed through a fairly fine sieve. You don’t want to just whizz crushed tomatoes in a food processer because you don’t want the flavor of tomato seeds in a passata.
It’s been a long time since I have used a canned tomato puree in America, but that would be closest in my recollection, provided it is not too salty. I would NOT use anything with added flavors (certainly in Italy, a great many recipes using a tomato passata would not also have garlic, and most recipes in Italy that use garlic do not also use onions in the same dish (one or the other). Certainly I would not use jarred marinara sauce.
If you have time to get Mutti passata, great. Mutti is a very high quality product.
By the way, here is a picture of passatelli pasta
You see what I mean about “passed through”. Here is picture of pomodori passata being made:
The end result is a bit thicker than American canned tomato sauce.
By the way, the word “passata” like “pesto” refers to a method, rather than an ingredient. Italians also make a passata of many other vegetables or legumes, and even fruits like apricots.
