Heat the oil in a large pot, or deep, large skillet over medium-high heat. Add the ground beef and sprinkle with the Italian seasoning, chili powder, salt, black pepper, and crushed red pepper, if using.
Arrange the beef in one layer and cook for 2-3 minutes. Stir well, arrange in one layer again and cook an additional 1-3 minutes until browned.
Lower the heat to medium and add the onions, cook for 3 minutes, stirring frequently.
Next, add the garlic and tomato paste, cook for 1 minute, stir often.
Add the pasta sauce, diced tomatoes, beef broth and Worcester sauce to the pot while stirring and gently scraping any browned bits off the bottom of the pot.
Raise the heat to high and bring the sauce to a simmer. Then, lower the heat to medium-low, cover the pot and let the sauce simmer for 10-12 minutes to let the flavors develop and come together.
Finally, add the macaroni to the pot, raise the heat to high and let the sauce come back to a simmer. Then, lower the heat to medium to medium-low to keep the sauce simmering, not boiling.
Cover the pot and cook the macaroni in the sauce for 12-15 minutes or until it is tender. Stir the macaroni often (especially in the beginning) because it tends to sink and will stick to the bottom of the pot.
Taste the macaroni and beef and add salt if needed. As a reference we added ½ teaspoon to ours.
Let the beef and macaroni sit in the pot for a few minutes before serving to give the macaroni noodles some time to soak up the tomato sauce. Serve with shredded cheese, or parmesan cheese, if desired.