Bring a large pot of salted water to a boil, then cook the pasta until al dente according to the package directions. The pasta should still have a little bite since it will finish in the sauce.

While the water heats, whisk the corn starch into the half-and-half until no lumps remain. This quick slurry helps the sauce hold together and gives it a silky body.

Melt the butter in a skillet over medium-low heat, then add freshly ground black pepper and cook for about 1 minute. The pepper should smell warm and fragrant as its oils bloom in the butter.

Pour the half-and-half mixture into the skillet and stir well, then bring it just to a simmer over medium heat. You want small bubbles around the edge, not a hard boil.

Take the skillet off the heat and stir in the grated Parmesan a little at a time until melted. The sauce should look glossy and be thick enough to coat the back of a spoon.

Stir in the truffle sauce and season with salt to taste. The truffle flavor should seem slightly stronger than you want at this point because it softens once the pasta is added.

Drain the pasta, add it to the skillet, and toss until every piece is coated. The sauce will settle into the pasta and turn creamy, earthy, and glossy.

Serve right away with more Parmesan and a little extra truffle sauce, or fresh shaved truffles if desired. The aroma is best while the pasta is hot, so this is the moment to get it to the table.