Spaghetti with Lobster Fra Diavolo

INGREDIENTS 2 tablespoons extra-virgin olive oil 1/2 medium onion, finely chopped Yellow Onions 4 garlic cloves, crushed 1/2 teaspoon red-pepper flakes 2 cans (28 ounces each) whole peeled tomatoes with juice, preferably San Marzano, pureed 2 cups water Coarse salt and freshly ground pepper 4 cups lobster stock or fish stock 3 lobster tails in shells 1 pound spaghetti 2 tablespoons chopped fresh basil DIRECTIONS 1. Heat oil in a large pot over medium heat. Cook onion, garlic, and red-pepper flakes, stirring occasionally, until soft and fragrant, about 10 minutes. Add tomatoes and water. Bring to a simmer. Cook until reduced by half, about 1 1/2 hours. 2. Season with 1 tablespoon salt and some pepper. Add stock and lobster tails. Cook for 30 minutes. Transfer lobster tails to a plate; let cool slightly. Remove meat from shells; cut in half lengthwise. Discard shells, and return meat to sauce. 3. Bring a large pot of salted water to a boil. Cook spaghetti until al dente. Drain, and transfer to a platter. Stir basil into sauce, ladle over pasta, and toss.