With the rack in the middle position, preheat the oven to 350°F (180°C).
In a large Dutch oven over medium-high heat, brown the meat in 2 tbsp of the butter. Season with salt and pepper. Set aside on a plate. In the same pot, soften the onions in the remaining butter, about 10 minutes. Add more butter as needed. Cook over high heat for 15 minutes or until the onions are caramelized, stirring constantly and scraping the bottom of the pot.
Add the broth, carrot juice, spices and lemon. Return the meat to the pot. Bring to a boil. Generously season with salt and pepper.
Cover and bake for 2 hours, turning the meat halfway through cooking. Remove the lid and continue cooking for 1 hour or until the meat is fork-tender. Remove the cinnamon stick and lemon. Adjust the seasoning.
Serve with mashed potatoes or with couscous with carrots and olives (see recipe).