A homemade Indian spice blend makes this lamb dish authentic and delicious.
Place lamb shanks in a single layer, and season with 1/2 teaspoon salt and lots of black pepper. Pat gently to adhere. Set aside.
In a blender, combine chopped ginger and 5 tablespoons water. Blend until smooth. Set aside.
In a spice grinder, combine nutmeg, mace, fennel seeds, bay leaves, and cinnamon. Grind as finely as possible. Transfer to a small bowl. Stir in ground ginger. Set aside.
Preheat oven to 325 degrees. Pour oil into a large saucepan over high heat. Add lamb shanks, and brown lightly on all sides. Remove, and set aside. Quickly add fresh ginger paste, and cook, stirring, until lightly browned, 5 to 6 minutes. Add cayenne pepper and paprika. Stir once or twice, then add half of the fried onion slices, well crumbled, ground spices, 3 cups water, and remaining 1 3/4 teaspoons salt. Stir well. Return lamb shanks to pan, spoon some sauce over, and bring to a boil. Cover with parchment-lined foil and the lid, and bake slowly in the oven for 3 hours, turning shanks every 30 minutes.
Remove pan from oven, and uncover. Spoon off as much oil as possible from the top, and discard. Taste, and season with salt, if necessary.
In a glass measuring cup, stir to combine 1/4 cup of water and flour. Pour into pan to thicken the sauce. Cook, stirring, over low heat for 5 minutes.
Serve with remaining fried onions, julienned ginger, chiles, cilantro, and lemon wedges on the side for garnish.