> 1. How are they stored best? Should I leave them in the bag in the
> fridge, or should I put them in a jar?

If you live in a hot tropical place, store it in your fridge but i assume
you're in the UK, so somewhere dry is fine.

> 2. How should I use them? I previously used black beans that were
> stored in oil and were ready to use. These 'Yang Jiang Preserved
> Beans'are harder, so do they require soaking? If so, for how long do I
> soak them for?

Soak them in a little warm or hot water until soft & tender. Drain & pound
in mortar & pestle with ginger, garlic, a little salt & sugar. Marinade meat
with this & you can also add a little rice wine. Fry on high heat to release
the pungent flavours.

DC.