Lamb Stuffed with Roast Garlic and Spinach 
There are few main course more festive than a beautifully browned roast stuffed with a savory filling. Buy an 8-pound leg of lamb and have the butcher bone and trim it into a boneless roast of about 5 pounds, trimming away almost all of the fat on the outside of the leg. Ask the butcher to saw the bones into large pieces for the sauce.
 

Ingredients
Sauce Base:
2 pounds lamb bones, sawed by the butcher into pieces about 4-inches
long
1 medium onion, quartered
1 medium carrot, coarsely chopped
1 medium celery rib, coarsely chopped
1 cup dry red wine
3 parsley springs
1/2 teaspoon dried thyme
2 garlic cloves, crushed
1 bay leaf
1/4 teaspoon whole peppercorns

Stuffing:
1 head garlic, separated into unpeeled cloves (about 12 plump cloves)
2 tablespoons olive oil, divided
1/4 cup pine nuts
1 medium onion, finely chopped
2 (l0-ounce) packages frozen chopped spinach, thawed and squeezed
well to remove excess moisture
1/2 cup dried unseasoned breadcrumbs
1/2 cup freshly grated Parmesan cheese
2 large eggs, beaten
1 tablespoon chopped fresh rosemary or 1 1/2 teaspoons crumbled
dried rosemary
1/2 teaspoon salt
1/4 teaspoon freshly ground pepper
1/8 teaspoon grated nutmeg
1 (5-pound) boneless leg of lamb, trimmed, untied
1 tablespoon olive oil
1/2 teaspoon salt
1/4 teaspoon freshly ground pepper
 

 Directions
1. Make the sauce base: Position a rack in top third of oven and preheat to 450°F. Place lamb bones in a large baking pan and bake until beginning to brown, about 45 minutes. Add onion, carrot and celery and continue baking until bones are deeply browned, about 30 additional minutes. Transfer bones and vegetables to a medium saucepan and discard fat in pan.
2. Place the roasting pan over high heat. Add 1 cup red wine to pan and scrape up browned bits on bottom of pan with wooden spoon. Pour into saucepan with bones. Add enough cold water to cover bones by 1 inch. Bring to a boil over high heat, skimming off any foam rising to surface. Reduce heat to low. Add the parsley, thyme, garlic, bay leaf and peppercorns. Simmer gently until reduced to about 3 1/2 cups, 2 to 2 1/2 hours. Strain the sauce base in a medium bowl. (The sauce base can be prepared up to 1 day ahead, cooled, covered and refrigerated.)
3. Make the stuffing: Reduce oven to 400° F. In a small bowl, toss the garlic cloves with 1 tablespoon of the oil. Place in center of a 12-inch square of aluminum foil and fold to enclose tightly. Place foil packet on a baking sheet and bake until garlic is tender, about 20 minutes. Unwrap the garlic and cool until easy to handle. Using a small, sharp knife, peel garlic, leaving cloves as whole as possible, set aside.
4. In a dry, medium skillet over medium heat, cook the pine nuts, stirring often, until toasted, about 3 minutes. Transfer the pine nuts to a plate and set aside.
5. In same skillet, heat oil over medium heat. Add the onion and cook until softened, about 5 minutes. Transfer to a medium bowl and add the garlic cloves, pine nuts, spinach, bread crumbs, Parmesan cheese, eggs, rosemary, salt, pepper and nutmeg; mix well.
6. Open up the lamb roast, fat side down, on a work surface. Using a sharp knife, butterfly the thickest pieces of meat and open them out to extend the length of the lamb to about 14 inches. (To butterfly the lamb, make deep cuts into the thickest parts of roast almost parallel to the work surface, but not cutting through meat. Open up resulting flaps, and meat will eventually become of a more even thickness and longer at the same time.)
7. Spread spinach mixture evenly onto lamb roast, leaving a 1-inch border around all sides. Starting at a short end, roll up the roast and tie crosswise and lengthwise with kitchen twine. Brush with the olive oil and season with salt and pepper. (The roast can be prepared up to 4 hours ahead of baking, covered with plastic wrap and refrigerated.)
8. Preheat the oven to 450°F. Place the roast on a rack in a roasting pan. Roast for 10 minutes. Reduce heat to 350 degrees and continue roasting until a meat thermometer inserted in the center of the roast reads l30 ° F. for medium-rare meat, about 2 hours. Transfer the roast to a serving platter and let stand for 10 minutes before carving.
9. Discard all fat in pan. Place pan on top of stove (over two burners, if necessary) and pour in sauce base. Bring to a boil over high heat, scraping up browned bits on bottom of pan with a wooden spoon. Boil until sauce is thickened and reduced to about 1 1/2 cups, 8 to 10 minutes. Pour into a warmed sauceboat.
10. Discard string from roast. Using a long, sharp knife, cut crosswise into thick slices.1Serve immediately, drizzling a few spoonfuls of sauce over each serving.