1. Season lamb shanks with salt and pepper. Heat oil in a large, heavy pot over medium-high heat. Working in batches if necessary, brown lamb shanks on all sides, about 4 minutes per side. Transfer lamb shanks to a bowl.

2. Add onions, garlic, ginger, cinnamon, coriander, cumin, and cayenne to drippings in pot, and cook 4 minutes. Return lamb and any juices to pot, and add enough water to cover (about 5 cups). Add honey, 1/3 cup cilantro, and the saffron, and bring to a boil. Cover, reduce heat, and simmer gently until lamb is tender, about 2 hours.

3. Meanwhile, bring 4 cups water to a boil. Add quinces and lemon juice. Cover with parchment cut to fit pan. Reduce heat, and simmer gently until tender but not falling apart, about 40 minutes. Drain, and then remove cores. Transfer half the quinces to a food processor, and puree. (Alternatively, mash with a fork.)

4. Place lamb on a plate. Raise heat to medium-high, and simmer to reduce liquid by half, about 20 minutes, skimming fat. Return lamb to pot, and add whole and pureed quinces. Cook until sauce has thickened, 20 to 25 minutes.

5. To serve, season tagine with salt and pepper. Spoon couscous into bowls, top with tagine, and sprinkle with remaining 2/3 cup cilantro and the almonds.