Heat the olive oil in a large saucepan over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic, diced carrot, and diced celery. Cook for an additional 5 minutes, stirring occasionally until the vegetables soften.
Increase the heat to medium-high and add the ground beef and ground pork to the pan. Use a spatula to break the meat apart, cooking until browned (around 7-10 minutes).
Once the meat is browned, drain any excess fat from the pan.
Add the crushed tomatoes, tomato paste, and beef broth to the meat mixture. Stir to combine.
Season with oregano, basil, salt, and pepper. Toss in the bay leaf for added flavor.
Reduce the heat to low, cover the saucepan with a lid, and let the sauce simmer for at least 30 minutes (up to 2 hours for deeper flavor), stirring occasionally and adding a splash of water if the sauce becomes too thick.
Taste and adjust the seasoning if necessary, then remove the bay leaf before serving.
Notes
Serve over your choice of pasta, topped with freshly grated Parmesan and chopped parsley.