For the braised lamb neck, preheat the oven to 200C/180C/Gas 6.
Pat the lamb neck dry. Heat a tablespoon of the olive oil in a large sauté or frying pan. Add the lamb neck and cook for 2–3 minutes to seal on all sides. Set aside.
Heat the remaining oil in a large flameproof casserole. Add the carrots, tomatoes, fennel, garlic, onion, red pepper, cardamom pods, fennel seeds and curry powder. Season with a pinch of salt and gently fry for 8–10 minutes, or until the vegetables are beginning to soften. Add the tomato purée and stir for another minute.
Add the wine, stirring to deglaze the pan, and boil until the wine evaporates. Add the lamb stock, bouquet garni and the lamb neck. Season with salt and pepper. Cover the casserole and bring the stock to the boil. Transfer to the oven and leave the lamb to braise for 3–3½ hours, or until the meat is tender enough to flake from the bone. Season the lamb with salt, pepper and cumin. Cover with kitchen foil and set aside.
Meanwhile, for the ragoût, bring a small saucepan of salted water to the boil and place a bowl of iced water in the sink. Add the carrots to the boiling water, blanch until just tender and drain well. Plunge into the iced water. Once cool, drain well and set aside.
About 10 minutes before serving, heat the oil in a sauté or frying pan. Add the lardons and gently fry until they render their fat and are coloured all over. Set the pan aside.
Strain the lamb cooking juices through a fine sieve into a saucepan and boil until reduced by half. Season with salt and pepper, if necessary.
To finish the ragoût, add the peas, blanched carrots and 150ml/5fl oz of the reduced cooking juices to the pan with the lardons. Leave to simmer for 3–4 minutes, or until the peas are tender. Stir in the lettuce and continue simmering until it wilts. Season with salt and pepper, if necessary.
Transfer the ragoût and lamb neck to warmed plates and serve immediately with the remaining cooking juices alongside.