Cook the pork, beef, and veal in a large pot over medium heat until browned.
Add the onion, garlic, celery, and carrots, and continue cooking until the vegetables have become tender.
Combine the crushed tomatoes, tomato paste, red wine, beef broth, black pepper, salt, nutmeg, and cloves in the pot.
Set to a low simmer and cook for at least two hours, stirring occasionally, or until the sauce has thickened.
Add the heavy cream and cook for an additional five minutes.
Your Bolognese sauce is ready to serve!