Put lamb, onion, garlic, sweet potato, turmeric, cinnamon, and saffron in large mixing bowl. Mix together until fully incorporated.
Place everything in bottom of tagine or heavy duty pot.
Pour just enough water to cover everything (this amount varies depending on how big your cooking vessel is).
Bring to a boil and then reduce heat to medium low and simmer. Cover and cook for 1 1/2 hours (or until meat is tender and cooked through). Stir occasionally. If using a tagine watch carefully because the water can easily boil over the low edges.
Serve with wild rice or couscous.