1/4 cup extra virgin olive oil
4 pounds oxtail (weighed with bone) or 3 pounds beef shank, well trimmed of fat and cut into 2-inch pieces
1 tablespoon pork lard
2 medium onions, finely chopped
1 pound potatoes, peeled and diced
2 cups beef broth
1 cup dry red wine
Bouquet garni, tied in cheesecloth, consisting of 5 sprigs fresh parsley, 15 sprigs fresh thyme, and 5 sprigs fresh savory or tarragon
Peel from 1 orange, without the white pith, in one long spiral
1 medium-size onion, peeled and studded with 1 clove
1 bay leaf
1 garlic clove, peeled and crushed
1 tablespoon tomato paste
1/4 cup chopped imported pitted green olives
1/4 cup chopped pitted black Nicoise olives
Salt and freshly ground black pepper to taste

1. In a large heavy casserole, heat the olive oil over medium-high heat, then brown the oxtail or shank pieces on all sides, about 5 minutes. Remove the oxtails from the casserole and set aside, keeping them warm.
2. In the same casserole, melt the lard over medium-high heat, then cook the chopped onions and potatoes until the onions are golden, about 8 minutes, stirring frequently and adding small amounts of water to scrape the browned bits off bottom of the casserole if necessary.
3. Return the meat to the casserole. Pour in the beef broth and wine along with the bouquet garni, orange peel, whole clove-studded onion, the bay leaf, garlic, tomato paste, and chopped olives. Season with salt and pepper.
4. Reduce the heat to low and simmer, uncovered, until the sauce is thick and the meat tender and falling off the bone, about 4 hours. Remove and discard the orange peel, bouquet garni, whole onion, and bay leaf. Serve immediately.