Ingredients
5 pounds mixed beef bones, such as marrow, neck, and oxtail
1 pound beef chuck (or other stew meat, cut into 1-inch pieces)
3 carrots, peeled
1 large onion, skin on, halved
Extra-virgin olive oil, for drizzling
2 celery stalks, plus a handful of inner leaves
1 teaspoon black peppercorns
2 thyme sprigs
6 parsley sprigs
Preparation
Preheat oven to 425°F. In a roasting pan, combine beef bones, stew meat, carrots, and onion. Drizzle with oil, tossing to evenly coat, and spread in a single layer. Roast, turning everything once halfway through, until meat is browned on all sides, about 45 minutes.
Transfer bones, meat, and vegetables to a stockpot. Place roasting pan over two burners, add 1/2 cup water, and bring to a boil, scraping browned bits from bottom; transfer mixture to stockpot. Add enough water to pot to cover meat and vegetables by about 2 inches (5 to 6 quarts). Bring to a boil, skimming foam and impurities from surface.
Add celery stalks and leaves, peppercorns, thyme, and parsley sprigs. Reduce heat to medium-low and gently simmer, uncovered, until mixture is darkened and reduced slightly, and bones have released their marrow, 8 to 12 hours.
Strain stock through a fine-mesh sieve (line it with cheesecloth for clearest possible stock). Let stand until fat rises to surface, then skim it from stock with a spoon. Freeze fat to use in place of oil or schmaltz in savory dishes. Stock can be refrigerated in an airtight container up to 1 week, or frozen up to 6 months.
