Bring a large pot of salted water to a boil.

Add tagliatelle and cook according to package instructions until al dente.

Reserve 1 cup of pasta water before draining.

In a large pan, melt the butter over medium heat.

Add Parmesan cheese and stir until melted and combined.

Add the heavy cream and parsley to the pan and stir to create a creamy sauce.

Add the cooked tagliatelle to the pan and toss until coated with the sauce.

If the sauce is too thick, add some of the reserved pasta water to thin it out.

Add the sliced truffles to the pan and toss until combined.

Season with salt and pepper to taste.

Serve hot, garnished with additional Parmesan cheese and fresh parsley.