Note: Seafood Stock can be made from fish-flavored bouillon cubes, available in most supermarkets. Bring a large pot of water to a boil over high heat. In the meantime, make the pepper sauce. Put the roasted peppers, shallots, garlic and vinegar in a blender and puree until smooth. Add 1/2 cup of the seafood stock and the basil and mix until blended. Transfer the mixture to a small saucepan, cover, and warm over the lowest heat setting. For the cilantro pesto, put the walnuts, garlic and cilantro in the bowl of a food processor. Turn the machine on and add 1 tablespoon of the seafood stock through the feed tube. Drizzle in the lemon juice to form a paste. Transfer the contents of the food processor to a small mixing bowl and whisk in another 3 tablespoons of the stock. When the water comes to a boil, add the pasta to the pot. Cook for 8 to 10 minutes, to desired tenderness. Drain. Dust the scallops with the blackening seasoning, paprika and thyme. Heat a heavy frying pan for 2 to 3 minutes over medium heat. Spray the pan with vegetable oil. Add the prepared scallops and sear them for 2 minutes on each side. Reduce the heat to low and squeeze the lemon over the scallops. Cover and cook for 5 minutes, until the scallops are firm. Return the drained pasta to the pot. Over low heat stir in the cilantro pesto. Divide the pasta among 4 bowls. Place 4 scallops on top of each and pour the pepper sauce over the scallops.