The Glamorgan sausage or "Selsig Morgannwg" as they say in the Old Language is a traditional dish from the county of Glamorgan (obviously) in South Wales. Unlike other sausages, it is an entirely vegetarian concoction containing a mixture of breadcrumbs, Caerphilly cheese and chopped leeks bound together with egg and seasoned to taste. It is not of course, obligatory to use Caerphilly cheese and some people will substitute the leek with spring onions or in desparation plain old ordinary onions.

The basic principle is that you mix together two parts of fresh breadcrumbs to one of grated cheese, add some chopped leaks and seasonings (mustard powder, herbs, whatever) add a beaten egg to bind it altogether; dip the result in egg white, cover it in flour and dried breadcrumbs and fry. (Just like a fishcake except with cheese, really.)

You are obviously supposed to roll it out into a sausage shape first, otherwise it wouldn't be a sausage, but I expect that the Welsh food police will turn a blind eye if you insisted on making them into balls or whatever took your fancy.

You can find various recipes at;

http://www.red4.co.uk/Recipes/glamorgan-sausage.htm
www.sausagelinks.co.uk/recipe_detail.asp?id=37
http://thefoody.com/cheese/glamorgansausage.html