Bring a large pot of salted water to a boil. Add the fettuccine pasta and cook according to package instructions until al dente, about 10-12 minutes. Drain the pasta and set aside.
In a large skillet or saucepan, melt the butter over medium heat. Add the minced garlic and sauté for 1 minute until fragrant, being careful not to brown it.
Pour in the heavy cream and bring to a gentle simmer. Reduce heat to low and cook for 5 minutes, stirring occasionally.
Gradually whisk in the grated Parmesan cheese until the sauce is smooth and creamy.
Season the sauce with salt, black pepper, and ground nutmeg. Stir well to combine.
Add the cooked pasta to the sauce and toss to coat evenly.
Remove from heat and stir in the chopped fresh parsley.
Allow the pasta Alfredo to cool completely, then transfer it to an airtight container.
Refrigerate for up to 2 days. To serve, reheat gently on the stovetop over low heat, stirring occasionally until warmed through. Add a splash of milk or cream if the sauce is too thick.