In a large, very heavy bottom 5 quart pan heat the olive oil and butter over medium heat and stir until combined. Cook onion, stirring often, until onion is soft, about 5 minutes.
Add celery and carrot to the pan and cook for 2 minutes, stirring to coat all the veggies well with oil mixture.
Add the ground beef and pork and 1 1/2 teaspoons salt and 1/2 teaspoon black pepper, breaking up the meat with a wooden spoon and cooking until the meat are no longer red or raw.
Turn the heat down to medium-low and add the milk and nutmeg. Simmer gently, adjusting heat lower as needed to maintain a gentle simmer, stirring frequently, until most of the milk has evaporated, about 1 hour. (Hazan says until the milk is completely gone but I simmered it until the meat was still moist and there was a little bit of liquid left in the pan.)
Add the wine to the pan and continue to gently simmer as before, stirring often for about 1 1/4 hours. (Again, Hazan says until the milk is completely gone but I simmered it until the meat was still moist and there was a little bit of liquid left in the pan.)
Pour in the crushed tomatoes and stir well to combine. Adjust heat as necessary to maintain the"laziest of simmers, with just an intermittent bubble breaking through the surface."
Continue to cook, uncovered for 3 hours, stirring as needed. If sauce begins to dry out, the fat will separate from the meat. Add 1/2 cup of water as needed to keep the sauce from scorching and sticking to the bottom of the pan. Taste for seasoning and add salt and pepper to taste.
Add remaining 2 tablespoons of butter to hot, just cooked and drained pasta and toss with the sauce. Serve.