In a medium-sized bowl combine lamb, cumin, ginger and ground cinnamon.
In large pot heat 2 tablespoons of olive oil over medium-high heat. When the oil is hot, brown lamb cubes on all sides, about 5 minutes, work in batches if needed. Remove the lamb with a slotted spoon and transfer to a clean plate.
Turn down the heat to medium, add 1 tablespoon of olive oil. Add the onions and garlic, sauté until softened, stirring as needed, about 5 minutes.
Add carrots and squash to the pot, cook for 5 minutes or until the vegetables begin to soften.
Add the lamb, tomatoes, orange juice and zest, apricots, 1 cup of beef stock, cinnamon stick and dried bay leaf.
Bring the stew to a boil over high heat, stirring gently with a wooden spoon to get up all the brown bits from the bottom of the pot.
When the stew comes to a boil, cover and reduce to a simmer over low heat.
Cook until the lamb is tender, 1 to 1 ½ hours. Check and stir every 20 minutes.
Add olives and lemon zest to the pot. Cook covered about 10 minutes more.
Season with salt and pepper to taste.
Serve lamb hot with couscous and garnish with chopped parsley and sliced mint.
In a 2-quart saucepan, bring beef stock, olive oil, salt, and cinnamon stick to a boil. Add couscous, stir, cover and turn off the heat.
Let couscous sit for 10 minutes, then fluff with a fork to separate the grains.
Leg of lamb may be substituted for lamb shoulder. If bone in, make sure to factor in the weight of the bone (buy around 3 pounds of meat instead of 1 1/2 pounds).