Fill a large pot with water and add a generous pinch of salt. Bring to a boil, add penne pasta, and cook for 10-12 minutes until al dente. Drain and reserve 1 cup of pasta water.

In a large skillet, heat olive oil over medium heat. Add diced onion and minced garlic, stirring for about 5 minutes until onion is translucent.

Add ground beef, breaking it apart. Cook for 7-8 minutes until browned. Season with salt, pepper, and Italian seasoning.

Lower heat to medium-low, stir in heavy cream and reserved pasta water until desired sauce thickness. Add Parmesan cheese and stir until melted.

Add drained penne pasta to the skillet and toss to coat in sauce. Keep on low heat for a few minutes.

Remove from heat and garnish with more Parmesan cheese or parsley if desired. Serve hot.