Auricularia auricula-judae. It's a rubbery, gelatinous purple-brown fungus that resembles a human ear in form and size.

It's found most commonly on dead or dying branches of Elder trees (Sambucus spp).

It can be found almost any time of year - either in active growth during wet spells in autumn, or in dried form - because in dry weather, it completely dessicates, shrinking into little crispy blue-black curls as seen here.

The good news is that it's perfectly usable when found all dried up like this - in fact, it's pretty convenient - because this is a mushroom that's useful for storage dried - and nature has done the hard work of preserving it.

The dried fungi just snap off easily by hand and can be dropped straight into a bag for storage - probably best to shake them first, in case there are any insects lurking inside the twists.

It didn't take me long to pick about a double handful of these dried mushrooms - I could have picked more, but we had gone to St Catherine's hill for a walk and I had fallen behind the rest of the group.

To use them, they first need to be rehydrated - this turned out to be a tremendously interesting process.

For a start, the dried mushrooms sink - I didn't expect that - but also, they soak up the water, visibly expanding and unfurling in just minutes - it's like watching those novelty paper flowers that open in a dish of water.

Once they're rehydrated, they've increased four or fivefold in size and they really do look like ears...

...Until they're sliced up (here with some sliced shallot leaves), then the look like rubber bands.

They smell sweet and pleasantly slightly fruity.

This is my first time tasting this fungus, so I wanted to cook them simply, so as not to lose them amongst lots of other ingredients and flavours.

So I sauteed them gently in a little butter, along with the shallot leaves - maybe for five minutes or so.

Then I finished them of with a splash of white wine and a few drops of soy sauce.

They don't seem to change much during cooking.