How to Make It
Heat the oven to 450°. In a large ovenproof pot, heat the oil over moderately high heat. Add the bacon and cook until the fat is rendered, about 5 minutes. Remove with a slotted spoon. Add about a third of the lamb. Brown well on all sides, about 8 minutes, and remove. Brown the remaining lamb in 2 more batches, adding oil if needed. Take the pot from the heat. Return the lamb to the pot with any juice that has accumulated. Stir in the bacon, chopped onion, garlic and flour. 2. Put the pot in the oven and cook, uncovered, stirring once or twice, for 10 minutes. Lower the oven heat to 325°. Return the pot to the stove. Add the tomato paste, tomatoes, stock and 1 1/2 teaspoons of the salt. Scrape the bottom and sides of the pot to dislodge any brown bits. Add the bouquet garni. Bring the stew to a simmer. Cover and return the pot to the oven. Cook until the lamb is almost tender, about 1 1/2 hours.
Meanwhile, in a large frying pan, melt the butter over moderate heat. Add the turnips, potatoes, carrots, small onions, the remaining 1/2 teaspoon salt and 1/8 teaspoon pepper. Cook the vegetables, stirring occasionally, until they begin to brown, about 10 minutes.
When the lamb has cooked for an hour and a half, add the browned vegetables to the pot. Bring back to a simmer on top of the stove and return to the oven. Cook until the vegetables are tender, about 30 minutes longer.
Meanwhile, bring a saucepan of salted water to a boil. Add the green beans and cook until tender, about 7 minutes. If using fresh peas, add them to the pan 4 minutes before the beans are cooked. Drain. Rinse with cold water and drain thoroughly. If using frozen peas, there is no need to cook them. Add the green beans, peas and 1/4 teaspoon pepper to the stew and simmer until warmed through, about 2 minutes. Remove the bouquet garni.