Heat olive oil in a large skillet over medium heat.
Add ground beef and cook until browned. Drain excess fat.
Add diced onion and garlic to the skillet. Cook until fragrant and softened.
Stir in uncooked pasta, beef broth, and marinara sauce. Bring to a boil.
Reduce heat, cover, and simmer for 12-15 minutes, stirring occasionally, until pasta is tender.
Sprinkle cheddar and mozzarella cheese on top. Cover and cook for 2-3 minutes, or until cheese is melted.
Season with salt and pepper to taste. Serve hot.