In a large soup pot or Dutch oven over medium-high heat, add the lean ground beef. Allow it to cook undisturbed for 5–6 minutes until browned, then gently break it apart with a wooden spoon.

Add the chopped onion to the pot, stirring to combine with the beef. Cook for an additional 5 minutes, allowing the onion to soften and become translucent.

Stir in the minced garlic, crushed red pepper flakes, and Italian seasoning. Sauté for about 1 minute until fragrant.

Mix in the uncooked orzo pasta, followed by the tomato sauce, beef broth, heavy cream, and Worcestershire sauce. Stir thoroughly until well combined.

Bring the mixture to a gentle bubble and reduce the heat to medium-low. Cook uncovered for about 10 minutes, stirring frequently to prevent sticking.

Once the orzo is cooked to your liking, remove the pot from heat. Stir in the freshly grated Parmesan cheese and baby spinach, mixing until the spinach wilts down.

Before serving, taste the dish and adjust with salt and pepper as desired. Give it one last stir to combine all the flavors.