Trim any excess fat from the lamb leg and cut the meat into 1-inch cubes.
Heat the olive oil in a heavy-bottomed pot or tagine over medium-high heat.
Add the lamb cubes to the pot and sear until browned on all sides, then remove and set aside.
In the same pot, add the diced onion, minced garlic, and sliced carrots, sautéing for 5 minutes until softened.
Stir in the ground cumin, ginger, cinnamon, sea salt, and black pepper to toast the spices for 1 minute.
Return the lamb to the pot along with the diced tomatoes and a splash of water or broth.
Cover and reduce heat to low, simmering for 35-45 minutes until the lamb is tender.
Stir in the cooked chickpeas and heat through for 2 minutes.
Serve the tagine over the warm cooked whole wheat couscous and garnish with fresh chopped parsley.