In a wide saucepan, heat olive oil over medium. Add diced pancetta and saute until slightly crispy, about 1 minute. Do not drain any fat that is rendered.
Add onion and cook until it begins to turn slightly translucent, about 1 minute. Add carrots and celery and cook another minute until all the vegetables begin to turn soft. Season with salt and pepper.
Add ground beef and pork. Break the meat down well with a spoon and cook over medium high heat until it begins to brown. Once browned, keep cooking until all traces of meat juice disappear. This can take up to 25 minutes. Once the beef juice has cooked off, add white wine. Continue cooking for another 5 minutes until the wine has also disappeared.
Add tomato paste and crushed tomatoes. Cook about 5 minutes to intensify the flavor of the tomatoes. Add water.
Bring the sauce to a boil over high heat, then reduce to a simmer. Cover and cook for a total of at least 3 hours, checking the consistency occasionally. For a thicker sauce, remove the lid. Add more water if necessary to loosen the texture to allow for proper cooking.
Add whole milk slowly so the sauce doesn't stop boiling. Simmer slowly for another 45-60 minutes. Give the sauce a final seasoning with salt and pepper and serve tossed with tagliatelle or pappardelle noodles.