Granddad comes every Sunday for dinner and he has got to have his soup. This was a special request as it reminds him of his childhood. In the old days, the lamb was cooked and removed from the pot, then the soup was made. The lamb that made the stock, was then served as the main course, with veg, if you were lucky. You can't make Scotch Broth, without the lamb it just wouldn't be Scotch Broth.
Prep time, does not include the overnight soaking, and cooking time excludes, the making of the stock.
If you brown your lamb first you will get more flavour.