Fusilli, Red Wine-braised Octopus, and Bone Marrow

In a heavy pot over medium-high flame, heat olive oil. Add onion, celery, carrot, garlic, and sachet. Reduce heat to medium and sauté 2 to 3 minutes. Add octopi and cook 5 minutes, or until they turn opaque and release some liquid. Add wine, bring to boil, and let the alcohol cook off for 30 seconds. Add tomato purée, stirring to combine. Season with salt, pepper, and peperoncino. Reduce heat to medium and simmer, covered, for 1 hour, until fork tender. Season bone marrow with salt and pepper. Heat a medium sauté pan over high flame until very hot. Add bone marrows and cook vigorously 1 minute, stirring with a wooden spoon. The marrow should sear but not melt completely. Drain seared marrow on paper towels; reserve liquefied marrow in a glass bowl. Bring a large pot of salted water to a boil. Add fusilli to the boiling water and cook 2 minutes less than specified on package instructions; drain and reserve 1 cup pasta water. Bring the red wine-tomato sauce back to a simmer. Add bone marrow and stir to combine. Add pasta to sauce and stir to combine. Add reserved bone marrow fat, which will emulsify into the dish. Season with salt and pepper, divide into four shallow bowls, and serve.