One of those soups many have heard of but never tried.
- Heat the oil in a large soup pot over high heat and brown the oxtails and onion halves in batches.
- Remove and set aside.
- Add the red wine to the pot and bring to a boil, stirring to scrape up all the brown bits in the bottom of the pot.
- Boil until the wine is reduced to about 2 tablespoons (30 ml).
- Add the reserved oxtails and onion and reduce the heat to low.
- Simmer covered for 20 minutes.
- Add the beef stock and bring to a boil over high heat.
- Skim off the foam that rises to the surface and simmer partially covered for 4 hours.
- Strain the soup and set the oxtails aside to cool.
- Pick off the meat from the oxtails and reserve.
- Refrigerate the meat and stock for up to 3 days.
- Skim off and discard the fat from the surface of the stock.
- Bring the stock to a simmer and add the reserved meat, sherry, carrot, celery, salt, and pepper.
- Simmer just until the vegetables are tender, about 10 minutes.
- Serve garnished with chopped parsley if desired.