I adore this recipe, even though it takes two days to make. Yep! That is right, two days. You could hurry things along and do it in a day, if you don’t have the time, but it is worth making the time for this recipe.
What takes so long is that there is roasting and simmering that takes place... The longer I do each step, the more intense this recipe gets. And how it smells while cooking is insanely good. Usually when I am planning a "stock making" weekend, I plan to do other things around the house that need to be done, so I don’t feel like it was a wasted weekend. Or, I indulge, by making stock and enjoying a few good movies or a book.
Head to the butcher and pick up your ingredients and then kick back and enjoy yourself; as soon as you pour yourself a bowl of soup made with this stock you will be thanking yourself (and me).
Preheat the oven to 325 degrees.
Season the marrow, oxtails, and beef shanks with salt and pepper, to taste. Place in a Dutch oven and coat with the olive oil. Roast until golden brown, about 3 hours.
Add the carrots, onion, and celery; stir and return to the oven. Roast for another 2 hours. Remove from the oven and place on the stovetop over low heat. Add the water and simmer for 3 hours.
Let cool and refrigerate overnight. The next day, skim off any fat that has hardened. Place back on the stove and continue simmering over very low heat for 4 more hours (or longer, if you can wait). Strain the mixture through a sieve, using a wooden spoon press the mixture to get out as much flavor as possible.
Pick off the meat from the shanks and bones and set aside. Return the broth and the bones to the Dutch oven. Simmer over very low heat for 2 more hours. Strain again and remove the marrow bones. Season with salt and pepper, to taste. Use immediately or freeze for future use.