In the past, people used as much of a slain animal as possible.
Internal organs were harder to preserve for a long time.
So the animal's stomach was used as a convenient natural casing,
which could be used to cook on the spot.
Traditional components of haggis
Chopped or minced 'pluck' of a sheep (heart, liver and lungs)
Coarse oatmeal
Suet
Spices (nutmeg, cinnamon and coriander are common)
Salt and pepper
Stock
This mixture is stuffed into a casing (nowadays sometimes synthetic rather than a stomach)
