Coat the bottom of a Dutch oven with a little olive oil and place over MEDIUM heat. Add the ground beef and pork. Crush and stir with a large spoon to break up until fully cooked, about 10 minutes. Use a slotted spoon to transfer the cooked meat to a dish and set aside. Drain the grease from the Dutch oven.
Add 2 tablespoons olive oil to the empty Dutch oven and return it to MEDIUM heat. Add the onion, carrots, and celery. Cook , stirring occasionally, for about 5 minutes, or until the vegetables have softened but not browned. Add the parsley, garlic and 1 teaspoon of salt. Stir well.
Add the cooked and drained meat to the Dutch oven with the vegetable mixture. Season the mixture with the thyme, oregano, nutmeg, the remaining 1 teaspoon of salt, and a generous amount of black pepper. Add the wine, increase the heat to MEDIUM-HIGH, and cook, stirring frequently, for about 5 minutes.
Add the tomato paste and stir it into the meat mixture. Add both cans of whole tomatoes, breaking the tomatoes up a little with the back of a spoon as you stir them into the meat mixture (they'll soften and be easier to break up later). Add the beef broth and milk and bring the mixture almost to a boil then turn down the heat to LOW. Cook, uncovered, for 1 to 3 hours. The sauce will be richer and thicker if it cooks longer. Check and stir occasionally, breaking up the tomatoes as they soften.
When ready to serve, boil the pasta according to the package directions. Drain the pasta (reserve a little pasta water) and return it to the hot, empty pan. Add the desired amount of the Bolognese and toss to combine. If the sauce has thickened more than you'd like, add a splash or two of pasta water to loosen it up a bit. Sprinkle in some grated Parmesan cheese, if desired.
Transfer to bowls and serve with additional Parmesan.