Heat butter and oil in a Dutch oven over medium heat. Add carrot, celery and onion and cook about 4 minutes until the onion softens. Add beef, breaking it into pieces with a wooden spoon; season with salt and pepper. Cook about 5 minutes, stirring often, until the beef is cooked through and browned in places. Add wine; cook about 2 minutes until it has reduced by half. Add milk; cook about 2 minutes until it has reduced by half. Add crushed and diced tomatoes and bring to a simmer. Lower heat to low, partially cover, and cook at least 1 hour or up to 2, stirring occasionally. Cook pasta according to the package instructions. Save 1/2 cup pasta cooking water, then drain and return to the pan. To serve, add 4 cups ragù, 1/4 cup reserved pasta water and 1/2 cup Parmesan to the pasta; stir. Use tongs to lift pasta and coat with sauce. If the sauce is too thick, add the remaining pasta water. Divide into bowls and top with more ragù, if desired. Serve with the remaining 1/4 cup Parmesan. TIP: For even richer flavor, simmer the sauce for 2 hours, adding a splash of water if it gets too thick. Freeze extra sauce for up to 1 month.