Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions until al dente.

Reserve 1 cup of pasta water, then drain the pasta in a colander.

In a skillet, heat the olive oil over medium heat. Add the minced garlic and sauté until fragrant, about 1 minute.

Pour in the heavy cream and bring to a simmer. Stir in the grated Parmesan cheese until melted and smooth.

Add the truffle oil, salt, and pepper to taste. If the sauce is too thick, add reserved pasta water a little at a time until desired consistency is reached.

Add the drained pasta to the skillet and toss to coat in the sauce.

Serve immediately, garnished with chopped parsley and truffle shavings if desired.