Preheat the oven to 350 degrees F.
Mix the ginger, saffron, olive oil, onion, and garlic together. Heat a large saute pan over medium-high heat. Add the oil mixture and cook until the onions soften, about 8 minutes.
Carefully add 2 cups of water to the mix and bring to simmer. Add the hens, skin side down into and cook for 10 minutes at a very low simmer. Remove only the hens to a baking dish, keeping the sauce warm over a low heat. Put the hens in oven and bake until it is cooked through, about 45 minutes. Serve on warm plate, hens first, then garnish with lemon and olives. Pour reserved sauce over hens.