Reestit Mutton

Does anyone know anything about how to cook with Reestit Mutton?
I was given some from my pal on Shetland and she makes a soup with kale and onions and potatoes.

Try this link it shows how to make soup with the mutton.
http://soup-aholic.blogspot.com/2006...ttie-soup.html

http://www.bbc.co.uk/radio4/factual/...shoulder.shtml

looks interesting if a bit drawn out.
Hope you find something you like.
River Cottage had a recipe too when googling

Cheers folks, will be giving it a try soon.