How to Make It
Bring a large pot of water to a rolling boil over high. Season lightly with salt. Add pasta, and stir gently with tongs. Boil until pasta is cooked but still slightly chewy, about 2 minutes.
While pasta cooks, melt 1/4 cup butter in a large skillet over high. Using tongs, transfer cooked pasta to skillet, and stir to evenly coat with butter. Use a ladle to add about 1 cup pasta cooking liquid to skillet, and continue stirring rapidly. Add remaining 1/4 cup butter, and shake and stir pan until the simmering water reduces slightly and forms a creamy sauce that clings to the pasta. Remove from heat, sprinkle pasta with cheese, and continue stirring until pasta partially absorbs cooking liquid and forms a creamy sauce. If pasta looks dry, add a splash more cooking liquid. Divide pasta among 4 bowls, and top with shaved truffles. Serve immediately.