01 - Heat olive oil in a large, heavy-bottomed pot over medium heat. Add onion, carrot, and celery; cook until softened, about 7 minutes.
02 - Stir in minced garlic and cook until fragrant, approximately 1 minute.
03 - Increase heat to medium-high. Add ground beef, breaking it up with a spoon, and cook until fully browned and no longer pink, about 8 minutes.
04 - Mix in tomato paste and cook for 2 minutes. Pour in red wine and simmer until mostly evaporated, about 3 minutes.
05 - Combine crushed tomatoes, beef stock, oregano, basil, black pepper, salt, and bay leaf. Stir thoroughly to meld ingredients.
06 - Lower heat to a gentle simmer and cook uncovered for 1 hour, stirring occasionally.
07 - Stir in whole milk and continue to simmer gently for 30 more minutes until sauce thickens and flavors deepen.
08 - Meanwhile, cook pasta according to package directions until al dente. Drain, reserving a small amount of pasta water.
09 - Remove bay leaf from sauce. Taste and adjust seasoning as necessary. Toss pasta with sauce, adding reserved pasta water if needed for desired consistency.
10 - Plate pasta topped with Bolognese sauce. Garnish with Parmesan cheese and fresh basil leaves if preferred.