If you have the time to make homemade beef stock, it’s always worth it.
Preheat oven to 400°F, with rack one rung above oven center.
In a large roasting pan, place bones, carrots, parsnip, parsley root (if using), celery, onions and garlic, season with salt, and drizzle to coat evenly with EVOO. Roast 45-50 minutes, turning bones halfway through. Carefully transfer bones and vegetables to stock pot, and add bay leaves, herb bundle and peppercorns. Place roasting pan over 2 burners on medium-high heat to loosen pan drippings with a couple cups of water. Loosen the bits, and pour over the bones and fill pot to cover bones and vegetables by three inches. Bring stock to boil, and reduce heat to simmer. Simmer 4-5 hours, skim any solids that float to the top. Strain stock, and store in fridge for up to 2 weeks or freeze for later use.