My stock boiled away for several hours, smelling delicious. Eventually I plucked out the head to see what I'd been left with. As with most heads there was a good amount of meat, and all the hours of boiling had actually done very good things to the tongue, but the brain was mush. Very close to the texture of wallpaper paste.
I picked the meat, and peeled the tongue. The broth was very strong, my thought is that they killed the lamb by inserting something into its head, which bled quite a bit (I discovered that after I cleavered the head open) so there was quite a bit of blood in the stock. Not something I thought about.
The scotch broth I made had loads of flavour, but to me seemed a tad gamier than it normally is. And I'm admittedly disappointed about not getting to try some yummy fried brains, or cold brains on toast.
I did, however, get a very flavourful (if maybe a tad gamey) bowl of soup.
"using virtually the entirety of any plant or animal"