Veal stock (brodo di vitello)

1.Preheat oven to 200C. Place veal shin in a roasting pan and roast until starting to brown (20-30 minutes), add all other ingredients and roast until browned (20-30 minutes). Transfer to a stockpot, add thyme and 3 litres cold water and bring to the boil over medium-high heat. Skim surface, then reduce heat to low and simmer, topping up water to keep shin covered, until stock is well-flavoured (3-4 hours). Strain through a muslin-lined sieve (discard solids). Veal stock will keep refrigerated for 3 days, or frozen for 3 months.