Prepare the frozen french fries according to the package instructions.

Remove the baking sheets from the oven. Drizzle with the truffle oil (note that if your bottle does not say “all natural”, drizzle to taste — it’s much stronger than all natural, so don’t use the quantity listed.) Add chunky sea salt, crushing it with your fingers as you sprinkle. Sprinkle with the Parmesan cheese. Serve immediately (fries become softer as they sit).