Heat pot over medium-high. Brown 900 g ground beef in the dry pot (or with 1 tbsp oil) until deeply browned; season lightly. Break into pieces but leave some larger crumbles for texture. Remove and set aside.
Reduce heat to medium, add onion and sauté 3–4 minutes until translucent. Add garlic and stir 30 seconds. Add 30 g tomato paste and cook 1–2 minutes.
Return browned beef to pot. Add 400 g crushed tomatoes and 960 ml beef broth. Stir in Italian seasoning and red pepper flakes. Bring to a simmer and cook 12–15 minutes to meld.
Stir in zucchini ribbons (or prepared shirataki noodles). Simmer 3–5 minutes until tender.
Reduce heat to low. Whisk in 113 g cream cheese until smooth; then fold in 226 g shredded mozzarella and 50 g Parmesan until melted and creamy. Adjust salt and pepper.
Serve hot, garnished with fresh basil or parsley and extra Parmesan.