Shrimp and Vegetable Tagine with Preserved Lemon

1. In a medium bowl, combine the parsley with the cilantro, lemon juice, paprika, ginger, saffron and olive oil. Add the shrimp, toss to coat and refrigerate for 2 hous. 2. Meanwhile, in a medium saucepan, combine the tomatoes with the garlic and cumin and season with salt and pepper. Simmer over moderate heat, stirring occasionally, until tomatoes are broken down and slightly thickened, 10 minutes. 3. Spread the slice carrots in a large enameled cast-iron casserole or Dutch oven and season lightly with salt and pepper. Add the onion, potatoes and bell peppers, lightly seasoning each layer with salt and pepper. Spread the tomatoe sauce on the top. Cover and simmer over moderatly low heat until the vegatables are just tender, about 20 minutes. 4. Add the preserved lemon and olives to the casserole and arrange the shrimp on top in a single layer. Season with salt and pepper. Cover and cood over moderately low heat until the shrimp are pink and curled, about 3 minutes. Transfer the shrimp to a plate. Raise the heat to moderate and cood the tagine uncovered, stirring once or twice, until the juices have evaporated, about 5 minutes. Don't let the vegatbles burn on the bottom. Transfer the vegatbles to a bowl and top with the shrimp. Garnish with cilantro twigs.