Heat 1 tablespoon olive oil in a large Dutch oven over medium-high heat until shimmering, about 1 minute.

Add ground beef, break into small pieces, and brown until no pink remains and a deep crust forms, 7–8 minutes. Transfer meat to a paper-towel-lined plate; drain excess fat, leaving about 1 tablespoon in pot.

Reduce heat to medium, add remaining tablespoon olive oil along with onion, carrots, and celery. Sauté until vegetables are softened and onion is translucent, 6–7 minutes. Stir in minced garlic and cook 1 minute more until fragrant.

Push vegetables to the sides, add tomato paste to center, and cook, stirring constantly, until paste darkens slightly, 1–2 minutes.

Pour in red wine (or additional broth) to deglaze, scraping up browned bits. Simmer until wine reduces by half, about 2 minutes.

Return browned beef to pot; add crushed tomatoes, beef broth, dried oregano, dried basil, bay leaves, sugar, salt, pepper, and red pepper flakes if using. Stir to combine and bring to a gentle boil.

Reduce heat to low and simmer uncovered, stirring occasionally, until sauce thickens and flavors meld, 30–40 minutes.

Remove bay leaves, taste, and adjust seasoning. Stir in chopped parsley, let sauce rest off heat for 10 minutes, then serve over pasta or use in desired dishes.