01 - Heat olive oil in a large heavy-bottomed pot over medium heat. Add pancetta and cook until lightly golden, about 3 minutes.
02 - Add onion, carrot, and celery; cook until softened and fragrant, approximately 8 minutes.
03 - Stir in minced garlic and cook for 1 minute to release aroma.
04 - Increase heat to medium-high, add ground beef, and cook until fully browned, breaking up clumps, about 5 to 7 minutes.
05 - Pour in red wine, scraping the pan to loosen browned bits, and simmer until mostly evaporated, about 2 to 3 minutes.
06 - Add tomato paste, crushed tomatoes, bay leaves, oregano, thyme, and optional nutmeg. Season with salt and pepper.
07 - Pour in milk and beef stock, then bring mixture to a gentle simmer.
08 - Reduce heat to low, partially cover, and simmer for 1.5 to 2 hours, stirring occasionally. Add additional stock or water if sauce thickens excessively.
09 - Taste the sauce, adjust salt and pepper as needed, and remove bay leaves.
10 - Meanwhile, prepare pasta in salted boiling water according to package directions, then drain.
11 - Combine pasta with sauce or serve the sauce ladled generously over pasta. Garnish with freshly grated Parmesan cheese.