When I was little and living in London, my mother used to buy pickles in a
barrel. In the same deli she also bought what she called "rollmops", but I
understand that name is incorrect since that's herring wrapped around a
pickle (or olive?).

I have tried herring in sour cream but it's much too bland. I can
approximate the taste I used to love by adding a lot of vinegar to the jar.
Is there a name for this so I can try to find it? Nostalgia has set in.

Dora