Jarred Pasta sauce is already cooked and ready to eat.
All you have to do is pour the Jarred Pasta Sauce onto the Pasta when ready and it's good to go.
Although I do like to heat the Jarred Pasta Sauce up first and then add the heated pasta sauce to the pasta.
But you don't need to cook the Jarred Pasta Sauce because it's ready to serve and eat.
When adding pasta sauce to the pasta it's best to pour the warm pasta sauce onto the pasta while the pasta is still hot.
And toss the pasta around in the sauce in the pan to mix the pasta sauce in with the pasta.
You don't want to cook the pasta in a cold pasta sauce as it can absorb too much of the pasta sauce and make it come out bad.