1. Heat the olive oil in a large Dutch oven or heavy-bottomed pot over medium heat. Add the finely chopped onion, carrots, and celery. Cook, stirring occasionally, until the vegetables are softened and translucent, about 8-10 minutes. This step is crucial for building the flavor base, so don’t rush it.

2. Increase the heat to medium-high. Add the ground beef to the pot, breaking it up with a spoon. Cook until the meat is fully browned and no pink remains, about 8-10 minutes. Drain any excess fat from the pot to prevent a greasy sauce. Season the beef with 1 teaspoon of salt and 1/2 teaspoon of black pepper.

3. Pour in the red wine, scraping the bottom of the pot with a wooden spoon to release any browned bits (fond). Let the wine simmer and reduce by about half, which should take 5-7 minutes. This step adds a wonderful depth of flavor.

4. Stir in the crushed tomatoes, diced tomatoes (with their juices), milk, heavy cream (if using), bay leaves, and a pinch of nutmeg. Bring the sauce to a gentle simmer, then reduce the heat to low.

5. Cover the pot partially, leaving a small gap for steam to escape. Let the Bolognese simmer gently for at least 2 hours, or up to 3 hours, stirring occasionally to prevent sticking. The longer it simmers, the richer and more complex the flavors will become, and the sauce will thicken. You’ll notice the sauce transforming into a deep, brick-red color with a velvety texture.

6. Remove the bay leaves. Taste the sauce and adjust seasoning with more salt and pepper as needed. Serve hot over your favorite cooked pasta, such as tagliatelle, pappardelle, or fettuccine. Garnish with fresh basil or parsley, if desired.