Laver is an edible seaweed that has high content of mineral salts, particularly iodine and iron. It is smooth and fine, often clinging to rocks.
Laver is common around the west coast of Britain and east coast of Ireland along the Irish Sea.
The two principal varieties are purple laver (Porphyra laciniata) and green laver (Ulva latissima). Another variety of sea spinach is called sloke (Porphyra palmata). This tends to be a brownish colour, but boils down to a dark green pulp when prepared.
The high iodine content gives the seaweed a distinctive flavour in common with olives and oysters.
Perhaps the best known of the edible seaweeds in Britain, laver is strong survivor of traditional regional cooking. It is widely used in Wales; in Scotland and Ireland (sloke) and Cornwall (black butter).
After the lengthy process of washing, soaking and long cooking, a dense, dark puree called laverbread is produced.
In Wales it is rolled in oatmeal and fried in round flat cakes to be served for breakfast with bacon.
A little mixed with stock and the juice and of a Seville orange makes traditional laver sauce for Welsh lamb or mutton.
A tiny amount spread on small triangles of hot toast makes an exquisite hors d’oeuvre, especially if topped with an oyster, shrimp or freshly steamed mussels.
It can also be used to enrich fish and shellfish sauces as well as an unusual ingredient for fish stuffing or mousseline.
Laver is used a great deal in Japanese cooking in the form of nori. The seaweed is processed by being chopped, flattened and dried on frames like paper.
It is used to wrap the delicate small parcels of vinegarard rice and fish that are eaten as sushi.
Held over a flame or put under the grill very briefly, the sheets of nori will crisp up and can be crumbled over seafood or other salads.
They can also be cut into shreds to decorate and flavour soups and salads.