1. Rub salt evenly over duck; cover and refrigerate 30 minutes.
2. Heat oil in a large Dutch oven over medium heat. Add bacon to pan; cook 7 minutes or until crisp, stirring occasionally. Remove bacon from pan using a slotted spoon; set aside. Increase heat to medium-high. Add lamb to drippings in pan; cook 8 minutes, turning to brown on all sides. Remove lamb from pan, and set aside.
3. Preheat oven to 300°.
4. Rinse duck with cold water; pat dry with paper towels. Add half of duck, skin side down, to pan; cook over medium heat 15 minutes or until golden brown. Turn duck over, and cook 10 minutes or until browned and fat under skin is melted. Remove duck from pan. Repeat procedure with remaining duck, reserving 1 tablespoon duck fat; set duck aside. Add onion and pepper to pan; cook 7 minutes or until lightly browned, stirring occasionally. Stir in tomato puree and garlic; cook 1 minute. Return lamb to pan. Nestle duck into lamb mixture; add broth and 2 cups water. Cover and bake at 300° for 2 1/2 hours or until lamb and duck are very tender. Remove duck from pan; let stand until tepid. Remove skin from duck; discard. Cut duck legs in half through the joint. Return duck to lamb mixture. Taste and adjust seasoning, if desired.
5. Increase oven temperature to 375°.
6. Stir 2 cans of beans into lamb mixture. Add bacon, sausage, and duck; top mixture with remaining 2 cans of beans. Sprinkle breadcrumbs evenly over top. Cover and cook 1 hour and 10 minutes. Uncover and cook an additional 20 minutes or until browned and bubbly.
Wine note: Traditionally, a rustic red from the south of France—a wine with the requisite meatiness and earthiness to mirror the duck and beans—is served with cassoulet. I love the Perrin & Fils Gigondas "La Gille" 2005 (Gigondas, France), $28, which is seductively earthy and has wonderful flavors of cherry jam. —Karen MacNeil