Place the spaghetti in a large saucepan and cover with 3 cups cold water; add a pinch of salt if using.
Bring the pan to a boil over high heat, then reduce slightly to maintain a steady boil; cook, stirring occasionally, until the water is mostly absorbed and the pasta is al dente, about 10 minutes—watch closely to avoid sticking.
While the pasta cooks, heat a large skillet over medium-high heat and add the ground beef.
Cook the beef, breaking it up with a spatula, until browned and cooked through, about 6–8 minutes.
Stir the jarred tomato and basil sauce into the cooked beef and simmer 1–2 minutes until heated through.
When the pasta is done and most of the water is absorbed, add the sauce and beef mixture to the pasta in the pan and toss to combine; alternatively, plate the pasta and spoon sauce over each portion.
Serve immediately, garnished with chopped fresh basil and grated Parmesan if desired.