Sausages have a reputation for being easy. They’ve got the right ratio of fat to meat built in, and even a convenient skin to ensure that all those juices stay inside. But there’s a difference between “yeah, that’s a good sausage” sausages and “holy crap, how did they fit an entire pig’s worth of flavor and juices into this single five-inch tube” sausages. It’s the latter we’re after, and the latter that sous vide cooking can help produce.
Source: The Food Lab’s Guide to Sous Vide Sausage | Serious Eats