Preheat your oven to 400°F. Toss the sliced carrots and cubed zucchini with half of the olive oil and a pinch of salt, then roast on a sheet pan for 20 minutes until tender.
While vegetables roast, heat the remaining olive oil in a heavy-bottomed pot or tagine over medium-high heat.
Trim any excess fat from the lamb shoulder, cut into 1-inch cubes, and sear in the pot until browned on all sides.
Lower the heat to medium and add the diced onion, minced garlic, and grated ginger, sautéing for 3 minutes until softened and fragrant.
Stir in the cumin, coriander, cinnamon, turmeric, sea salt, and black pepper, coating the meat thoroughly in the spice mixture.
Pour in the chicken bone broth and the rinsed chickpeas, scraping the bottom of the pot to release any browned bits.
Cover the pot with a tight-fitting lid and simmer on low heat for 35 to 40 minutes, or until the lamb is fork-tender.
Gently fold the roasted carrots and zucchini into the tagine and simmer for another 2 minutes to meld the flavors.
Garnish with freshly chopped cilantro and serve warm.