- In a large pan, melt the butter over medium heat. 
- Stir in the garlic and sauté for 1–2 minutes, just until fragrant. Don’t let it brown. 
- Pour in the heavy cream, salt, and white pepper. Stir it up and let it warm for about 2–3 minutes. 
- Slowly whisk in the parmesan cheese, stirring constantly until it’s fully melted and smooth. 
- Add in the mozzarella and continue stirring until you have a thick, creamy sauce. 
- Serve over hot cooked fettuccine and sprinkle with chopped parsley if you’d like.