1. Adjust oven rack to lower-middle position and heat oven to 300°F. Cut meat from bones and reserve bones. Trim meat of excess fat and cut into 1 1/2-inch cubes. Season meat generously with salt and pepper.

2. Heat 1 tablespoon oil in large ovenproof Dutch oven over medium-high heat until shimmering, about 2 minutes. Add half of meat to pot so that individual pieces are close together but not touching. Cook, without moving, until sides touching pot are well-browned, 2 to 3 minutes. Using tongs, turn each piece and continue cooking until most sides are well-browned, about 5 minutes longer. Transfer meat to medium bowl, add another 1 tablespoon oil to pot, and swirl to coat pan bottom. Brown remaining lamb; transfer meat to bowl and set aside.

3. Reduce heat to medium, add remaining tablespoon oil, and swirl to coat pan bottom. Add onions and 1/4 teaspoon salt and cook, stirring frequently and vigorously, scraping bottom of pot with wooden spoon to loosen browned bits, until onions have softened, about 5 minutes. Add garlic and cook until fragrant, about 30 seconds. Add flour and stir until onions are evenly coated, 1 to 2 minutes.

4. Stir in 1 cup of water and wine, scraping pan bottom and edges with wooden spoon to loosen remaining browned bits. Gradually add remaining 3/4 cup water, stirring constantly and scraping pan edges to dissolve flour. Add rosemary, tomatoes, and 1 teaspoon salt and bring to simmer. Add bones and then meat and accumulated juices. Return to simmer, cover, and place in oven. Cook for 1 hour.

5. Remove pot from oven and place potatoes and green beans on top of meat and bones. Cover, return pot to oven, and cook until meat is tender, about 1 hour. If serving immediately, spoon off any fat that rises to top. (Stew can be covered and refrigerated for up to 3 days. Spoon off congealed fat and bring back to simmer over medium-low heat.)

6. Stir in basil and adjust the seasonings. Remove bones if desired. Serve immediately.

Serves 6