Is "swimming in broth" a common cooking technique for pasta and broccoli rabe? In two "old school" Italian restaurants in New York, USA, I've ordered penne with sausage and broccoli rabe. Both times the pasta was served with a good 1/4 to 1/2 cup of liquid in the bottom of the dish.

I'm trying to figure out whether this liquid is chicken stock (it kind of tastes like it), and as such is part of the recipe, or whether it is leftover water from the cooking process (the broccoli rabe and penne were both overcooked).

A quick search of recipes for penne with broccoli rabe and sausage do not include stock as an ingredient.

Yet, the broth was quite flavorful, so I'd be surprised if it was only water.

Maybe "old school" Italian restaurants in NY use chicken stock in these dishes? Any insight?
I am not sure whether it is a common way to prepare it in the US, but I would say that it is definitely not the traditional Italian way to serve pasta salsiccia e friarielli which is instead a fairly dry pasta dish.

Of course nothing stops you from making variations on the theme. For instance, I know some people who purée the broccoli rabe.

However, in Napoli (where the dish is from) you would generally have it dry.