In a large Dutch oven or heavy bottom pot, heat the olive oil over medium to medium-high heat. Add onion, celery, garlic and carrot. Cook, stirring occasionally, until the vegetables are soft and golden, about 5-7 minutes.
Add the ground beef, pork, and pancetta to the Dutch oven. Use a wooden spoon to break the meat apart as it cooks, just until lightly browned. 5-7 min.
Add the tomato paste and chili flakes and cook for about 2 minutes stirring often.
Add the wine to deglaze and cook until the wine is reduced almost completely, about 8-10 minutes, stirring to scrape up any browned bits at the bottom of the pot.
Add the milk and simmer until it has reduced and evaporated, about 8-10 minutes, stirring often.
Stir in the tomatoes, broth, bay leaves, Italian seasoning, salt and pinch of black pepper.
Bring to a simmer then reduce the heat to low cooking at a very low simmer for 1-3 hours until the meat is tender and the sauce has reduced and thickened and deepened in colour.
Stir in the parmesan cheese and the chopped parsley or serve it on the side.
Serve the sauce over wide egg noodles or pasta noodles such as spaghetti, pappardelle, tagliatelle, fettuccine, or rigatoni, or toss the pasta in sauce.
