How to Make It
Season the pork bones with salt and pepper. In a large enameled cast-iron casserole, heat 2 tablespoons of the olive oil. Add the pork bones and cook over moderately high heat, turning, until they are browned all over, about 8 minutes. Transfer the bones to a plate.
Add the onion and garlic to the casserole and cook over moderately high heat until softened, about 8 minutes. Stir in the crushed and diced tomatoes, 1 cup of water and the fresh and dried herbs and bring to a simmer. Return the pork bones to the casserole and simmer over low heat until the meat is very tender, about 2 hours. Using a slotted spoon, transfer the bones to a plate and let cool slightly. Pick the meat from the bones and stir it into the gravy. Season the pork gravy with salt and pepper and keep warm.
In a small bowl, whisk the ricotta with the remaining 1 tablespoon of olive oil and season with salt and pepper.
In a large pot of salted boiling water, cook the ziti until al dente. Drain and return to the pot. Stir the pork gravy into the pasta and season with salt and pepper. Spoon the pasta into bowls, top with the ricotta cheese and serve.