• 1 lb. dry or fresh orecchiette, pappardelle or tagliatelle
• Freshly grated Parmigiano- Reggiano cheese, for serving
In a medium pot over medium heat, heat the butter and canola oil. When butter has melted, add onion and cook, stirring, until it begins to soften, about 6 minutes. Add celery and carrot and cook, stirring, for 3 to 4 minutes.
Add ground beef, a large pinch of salt and a few grindings of pepper. Cook the meat, breaking up the large chunks (with a wooden spoon) as it cooks, until beef is just cooked through, about 5 minutes. Pour in wine and cook, stirring occasionally, until almost all the wine has evaporated. Pour in the milk, add the nutmeg and bring to a gentle simmer. Add tomatoes and their juices and stir to combine. Bring to a boil, then reduce heat so sauce is at a very slow simmer, barely bubbling. Add bay leaf and cook, uncovered, for 2 1/2 to 3 hours, until meat is very tender and sauce is rich and concentrated, stirring from time to time with a wooden spoon. If the sauce begins to look too dry, add a bit of water; you don't want the sauce to break or become too dry, but the goal is a reduced, concentrated sauce, so don't overwater it.
Season to taste with salt and pepper. Bolognese can be made ahead; remove from heat and let it cool to room temperature, then transfer to a refrigerator. It will keep for up to 1 week or can be frozen for up to 3 months. Thaw before using.