4-5 Pounds Beef Marrow Bones
2 Large Spanish Onion, Skin On, Cut into Large Chunks
6 Large Carrots, Skin On, Cut into Large Pieces
1 Whole Bulb Garlic, Broken Apart
1 Small Can Tomato Paste
1 Tablespoon Whole Black Peppercorns
2 Bay Leaves, Broken in Half
Preheat oven to 425°F.
In a roasting pan toss the beef bones and vegetables with the tomato paste. Roast for 1 hour.
Place all of the bones and vegetables into a large pot such as a Dutch oven. Deglaze the roasting pan with water and scrape up the FOND and drippings and transfer to the Dutch oven. Add the whole peppercorns and the bay leaves. Cover with water by one or two inches. Bring the liquid to a rolling boil, reduce the heat to low and bring to a simmer. Cover with a lid. Let this simmer for at least twelve hours. It is most important to have the stock bubbling very slowly during the cooking time.
Strain the liquid into a fine messed sieve over a large bowl. Cool to room temperature and refrigerate. All of the fat will come to the top. Remove the fat and you will have a beautiful, rich, flavorful stock. You can divide it into several airtight containers and freeze for at least a month.