In a large skillet or Dutch oven, heat 1 tablespoon of olive oil over medium-high heat. Add the ground beef, season with a pinch of salt and pepper. Break it up with a spoon and cook until browned and crispy in spots, about 6-8 minutes. Drain excess fat if necessary.

Reduce heat to medium. Add the diced onion to the skillet with the beef. Cook until onions soften and become translucent, about 5 minutes. Stir in the minced garlic and tomato paste. Cook for 1 minute until the paste darkens and becomes fragrant.

Pour in the crushed tomatoes, broth, Italian seasoning, and red pepper flakes if using. Bring to a simmer and let bubble for 5 minutes to allow flavors to meld.

Meanwhile, cook the pasta in a separate pot of salted boiling water according to package directions until al dente. Drain well, reserving a bit of pasta water if needed.

Reduce heat to low. Stir in the heavy cream until the sauce turns a light orange-red color. Fold in the cooked pasta, half the basil, and half the Parmesan cheese. Stir until everything is coated.

Remove from heat. Garnish with remaining basil and extra Parmesan. Serve immediately.