In a frying pan or skillet, heat olive oil. Cook carrots, onion, celery, sage, and rosemary until softened.
Add the ground pork, ground veal, and chopped pancetta. Let the meat brown well over high heat, stirring constantly.
Add white wine and let the alcohol evaporate. Season with salt and pepper, add bay leaves and 2 ladles of hot stock. Simmer for about 1 hour, adding more stock as necessary.
In a frying pan or skillet, heat olive oil and cook garlic until slightly softened. Add mushrooms, cook for 5-10 minutes. Add the white wine and turn up the heat until the alcohol evaporates. Reduce the heat, stir in parsley, and cook for 1-2 more minutes.
Note: If the mushrooms seem dry, you can add some broth or pasta cooking water to them.
Ten minutes before the meat ragu is finished, remove bay leaves and add milk then simmer over low heat. While the white ragu simmers, bring a large pot of water to a boil for the pasta. Once boiling, add salt and bring to the boil again.
Cook the pasta al dente according to the instructions on the packet. Drain and mix with the white ragu sauce.
Serve topped with mushrooms, garnished with parsley, and optionally grated Parmigiano Reggiano or Grana Padano.