1. Preheat oven to 375 degrees.

2. Place bones in a large roasting pan; add oil and toss to coat. Transfer to oven and roast, turning occasionally, until golden brown, about 1 hour.

3. Spread onions, carrots, celery, and garlic over the bones. Spread tomato paste over vegetables and return to oven; roast for 45 minutes more.

4. Remove from oven and transfer bones and vegetables to a large stockpot; drain and discard fat from roasting pan, reserving juices in roasting pan. Add 24 cups water to stockpot, along with bay leaves, thyme, salt, and peppercorns. Bring to a boil over medium-high heat.

5. Meanwhile, place the roasting pan over two burners set to medium-high heat. Add wine to pan to deglaze and stir, scraping up any browned bits on bottom of pan; transfer liquid to stockpot and return to a boil. Reduce heat to low and simmer, uncovered, for 8 hours, skimming occasionally to remove any foam on the surface of stock.

6. Set a fine mesh strainer over a large pot. Remove bones from stockpot and discard. Ladle stock through the strainer and into the pot. Bring to a boil over medium-high heat and cook, uncovered, until reduced to 6 cups, about 1 hour. Let cool completely, cover, and refrigerate overnight. Remove any congealed fat from surface of stock.