Preheat the oven to 500°F.

Place beef or veal bones in a large roasting pan.

Brown the bones in the oven for 45 minutes to 1 hour, until deeply colored.

While the bones are browning, heat vegetable oil or butter in a large stockpot over high heat.

Add thickly sliced carrots and halved, sliced onions to the stockpot.

Cook, scraping the browned bits from the bottom of the pan, until the vegetables are well browned, about 20 to 25 minutes.

Add the browned bones to the stockpot.

Cover the bones with 8 quarts of cold water.

Add celery stalks, diced leeks (optional), turnip pieces stuck with cloves, garlic cloves, bouquet garni, and peppercorns.

Bring the mixture to a boil, which should take about 30 to 45 minutes.

Reduce the heat to low and simmer, uncovered, for 3 1/2 hours.

Skim the surface several times during simmering to remove any foam.

Strain the stock through a fine-mesh sieve.

Allow the stock to cool uncovered before refrigerating.

Once refrigerated, remove any fat from the surface before using.

Freeze the portion not used, or reduce to form a meat glaze (Glace de Viande).

To make Fonds Brun Rapide (Quick Beef Stock), combine all ingredients without browning into a pot, cover with water, and bring to a boil.

Blacken an onion by cutting it in half and placing the cut sides down in a hot, dry skillet for 3-4 minutes.

Add the blackened onion to the stockpot to give the stock a brown color.

To make Fonds de Gibier (Game Stock), follow the beef stock recipe but use 6 pounds of game meat and 7 pounds of bones, 10 juniper berries, and 2 sage leaves.