In a large skillet over medium-high heat, add the lean ground beef, chopped onion, and minced garlic. Cook for about 5-7 minutes, stirring frequently, until the beef is no longer pink and the onion is translucent.
Drain the excess fat if necessary. Add the stewed tomatoes (with juice), one can of water, dried parsley, dried oregano, red pepper flakes, salt, and pepper to the skillet. Stir to combine.
Bring the mixture to a boil, then stir in the elbow macaroni. Reduce the heat to low, cover, and simmer for about 15 minutes, or until the pasta is tender, stirring occasionally to prevent sticking.
Once cooked, serve hot with freshly grated Parmesan cheese on top. Adjust seasoning if desired.