Heat 1 tablespoon olive oil in a large deep skillet or pot over medium heat.

Add 1 pound ground beef. Break it up and cook until fully browned, about 5 to 6 minutes. Drain excess fat if you prefer less grease.

Stir in minced garlic, ½ teaspoon salt, ½ teaspoon black pepper, and ½ teaspoon red pepper flakes if using. Cook for about 1 minute until fragrant.

Pour in 3 cups beef broth and 2 cups milk. Stir and use a spoon to scrape any browned bits from the bottom of the pan.

Add 12 ounces pasta and 1 teaspoon Italian seasoning. Push the pasta down so it is mostly submerged in the liquid.

Bring the mixture to a gentle simmer. Cover and cook for 12 to 15 minutes, stirring occasionally to prevent sticking and to distribute heat evenly.

Reduce heat to low. Stir in ½ cup grated parmesan and 2 tablespoons butter until melted and the sauce becomes creamy.

Taste and adjust seasoning. If the sauce is too thick, add a splash more milk or broth and stir until you reach the desired consistency.

Garnish with chopped parsley and extra parmesan before serving.