Enjoyed these in Prague last week... Pickled Sausages, a pub specialty here from what I researched.
Basically a Knockwurst of sorts (pre-cooked type sausage) split and stuffed with peppers/onions and pickled for a few weeks, served with a side of rye.
It was phenomenal... (Or so I thought). I will absolutely be making these here now that I am back home! Served with a proper Czech Beer, of course.
Here in Cleveland, we have a handful of old world European sausage shops... Ukrainian, Polish, etc... My favorite being a Ukrainian butchery (State Meats, link below) that I basically grew up on at every holiday with their phenomenal fresh and smoked kielbasas.