Heat olive oil in a large skillet over medium-high heat. Add ground beef, breaking it apart. Season with salt, pepper, and Italian seasoning. Add red pepper flakes if desired. Cook for 6–8 minutes until browned and cooked through. Drain excess fat.

Reduce heat to medium, add minced garlic and unsalted butter to the skillet. Stir for 1–2 minutes until garlic is fragrant but not burnt.

Bring a pot of salted water to a boil. Cook cheese tortellini according to package directions for 3–5 minutes. Drain and set aside.

Add cooked tortellini (or uncooked if using fresh) to the skillet with beef and garlic. Pour in beef broth, stir gently and cover. Let simmer for 5–7 minutes.

Add chopped spinach to the skillet, stir gently for 1–2 minutes until wilted.

Stir in grated Parmesan cheese, mixing until melted. Adjust seasoning if needed.

Serve hot, topped with extra Parmesan and parsley if desired.