Add pancetta; sauté until fat is rendered, about 3 minutes.
Add onion and parsley and sauté until onion is soft, about 5 minutes.
Add ground pork and sauté until brown, breaking up with back of fork, about 8 minutes. Stir in crushed tomatoes, bay leaves, and sage. Reduce heat to medium-low and simmer until sauce thickens and flavors blend, stirring occasionally, about 25 minutes. Season sauce to taste with salt and pepper. (Can be made 2 days ahead. Chill uncovered 1 hour. Then cover and keep chilled. Rewarm over low heat.)
Meanwhile, bring large pot of salted water to boil.
Add pasta and saffron and cook until pasta is just tender but still firm to bite.