Preheat your oven according the frozen fry package instructions. Prepare a baking sheet and spread the fries evenly across.
Once fries are cooked and crispy, put them in a large mixing bowl. Sprinkle them with Parmesan cheese, truffle oil, parsley, and salt. Toss until the fries are well-coated.
Put the coated fries on the baking sheet again and bake for an additional 5 minutes.