I found a field with absolutely 100s of Pig Nuts. You need to have the land owners permission to dig them up.
You basically follow the very thin single route down into the soil and you will find the Pig Nut attached to the end. You have to be very careful when you do this or the Pig Nut will break off and they are very difficult to find in the soil.
You then carefully peel them with a knife and you can eat them either raw or cooked. They do taste a little nutty.
An amazing little foraging find!