01 - Bring a large pot of salted water to a boil. Cook the high-protein pasta according to package directions until al dente. Drain thoroughly and set aside.
02 - Heat a large nonstick skillet over medium-high heat. Add the ground beef and cook, breaking it apart with a spoon, until browned and completely cooked through, about 6 to 7 minutes. Drain any excess fat if needed.
03 - Add the chopped onion to the skillet and cook for 3 to 4 minutes until softened. Stir in the garlic and cook for 1 minute until fragrant.
04 - Add the chopped spinach to the skillet and stir until wilted, about 2 minutes.
05 - Reduce heat to low. Stir in the cream cheese and milk, mixing constantly until a smooth, creamy sauce forms. Add the Parmesan, Italian herbs, black pepper, and salt. Simmer gently for 2 to 3 minutes.
06 - Add the cooked pasta to the sauce, tossing gently to coat every piece evenly. Taste and adjust seasoning as needed. Sprinkle with extra Parmesan and red chili flakes if desired. Serve hot.