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