Preheat oven 425°Fahrenheit. Cut the onion, carrots, and celery into quarters. Place in a hot Dutch oven with the bones.

Place in the oven uncovered for 45 minutes. When the bones are almost done heat the beef broth and water.

Put the Dutch oven on the stove top. Add the beef broth and bring to a boil. Turn down to a simmer and simmer for 45 minutes.

Strain through a sieve. You have just made a beef stock.