For Sauce: Peel and butterfly shrimp, cutting underside of shrimp 3/4 of the way through. Clean out dark vein, rinse and dry. Rinse and dry shells. Saute shells in medium pot with 1 tablespoon olive oil. Add onion and garlic, color moderately for 2 minutes. Add tomato paste and stir for 2 minutes, then add wine and bundle of herbs. Reduce to half. Add 2 cups cold water and simmer for 30 minutes.;
For Stuffing: Sweat leeks in butter for 1 minute. Add sweet potato and cook 2 minutes. Add spinach, apple and tomato, stirring until all items are fairly soft, about 5 minutes. Add curry or cumin powder, cream and bread, stirring for 2 minutes. Away from heat stir in egg yolk, salt and pepper to taste. Let cool. Add 1 heaping tablespoon to open side of shrimp, lightly seasoned, folding over any tail section. Lay shrimps on lightly buttered baking dish, stuffing side up. Add strained stock (about 12 ounces) and bake at 375 degrees for 8 to 10 minutes, basting occasionally until just cooked. Reduce liquid as desired and whisk in chopped dill and 1 teaspoon olive oil. Season to taste.