Ingredients:

  • 4 lbs (1.8 kg) beef bones, such as marrow bones, knuckle bones, and oxtail
  • 2 tbsp (30ml) vegetable oil
  • 1 large yellow onion, roughly chopped (approx. 200g)
  • 2 carrots, roughly chopped (approx. 150g)
  • 2 celery stalks, roughly chopped (approx. 100g)
  • 4 cloves garlic, smashed
  • 1 (750ml) bottle dry red wine (e.g., Cabernet Sauvignon, Merlot)
  • 12 cups (2.8 liters) cold water
  • 1 tbsp (15g) tomato paste
  • 1 bay leaf
  • 1 tsp (5ml) black peppercorns
  • 1/2 tsp (2.5ml) dried thyme
  • 1/4 tsp (1.25ml) dried rosemary
  • 8 cups (1.9 liters) reduced brown stock (from above)
  • 1/2 cup (120ml) dry sherry or Madeira wine
  • 1 sprig fresh thyme
  • 1 bay leaf

Instructions:

  1. Preheat oven to 400°F (200°C). Toss bones with vegetable oil and roast until deeply browned, turning occasionally.
  2. In the stockpot, sauté the onion, carrots, and celery in the rendered fat from the bones until softened and lightly browned. Add the garlic and tomato paste and cook for another minute.
  3. Deglaze the pot with the red wine, scraping up any browned bits from the bottom. Reduce the wine by half.
  4. Add the roasted bones to the pot. Pour in the cold water to cover the bones. Bring to a simmer.
  5. Reduce heat to the lowest setting and simmer gently for 12-24 hours, skimming off any impurities that rise to the surface (the scum).
  6. Strain the stock through a fine-mesh sieve or cheesecloth-lined colander. Discard the solids. Let cool slightly, then refrigerate overnight.
  7. Remove the solidified fat from the surface of the chilled stock. A fat separator can also be used.
  8. Pour the defatted stock into a clean stockpot. Add the sherry or Madeira, fresh thyme sprig, and bay leaf.
  9. Simmer the stock over low heat, uncovered, until it has reduced to a glossy, slightly thickened sauce. This can take several hours, and will coat the back of a spoon.
  10. For a super-smooth demi-glace, strain the sauce one more time.
  11. Allow the demi-glace to cool completely before storing in an airtight container in the refrigerator for up to 5 days or in the freezer for up to 3 months.