It's just Branston Pickle, not
a pickle.
Branston's website.
It's cubed vegetables in a flavoured sauce. It's sweetish, but the little chunks still have a crispy bite. I suppose it's a cross between a relish and a chutney really.
If I ever find a place that does little catering samples I'll swipe one and send it to you.
It comes in glass jars, so postage is a bit on the heavy side otherwise.
ETA - you
can buy it in America.
I wouldn't necessarily say go for it though.
It's probably an acquired taste (I grew up with it) and it would be sad to waste a whole jar.