Brown the meat. Heat a large Dutch oven over medium-high heat and add then add the ground beef. Now, cook the beef until it’s no longer pink, breaking it up as you stir.
Add the onion, garlic, and pepper flakes. Add the onion, garlic, and red pepper flakes to the Dutch oven with the browned meat and cook for another 3 minutes or until the onion becomes soft and translucent.
Stir in the pasta, marinara, and seasonings. Stir in the tomato paste, marinara sauce, Italian seasoning, sugar, beef broth, salt, and black pepper. Now, bring it all to a boil and then turn the heat down to a simmer.
Add the pasta. Add the spaghetti to the Dutch oven and press the noodles down to submerge them in the sauce, but DO NOT STIR. Yet, the pasta must be fully covered in the sauce to cook properly.
Cook the pasta. Cover the Dutch oven with a lid and cook for 15 to 20 minutes stirring every 5 minutes. When the spaghetti is done all the liquid should be absorbed and the pasta cooked to al dente.
Garnish and serve. To serve, sprinkle the spaghetti with grated parmesan cheese and freshly chopped parsley.