Use frozen, bagged fries to have tasty truffle fries, covered in truffle oil, parmesan, and parsley on the table in less than 15 minutes. Preheat oven to 450F. Set up racks in the upper middle and lower middle positions.
Take out two baking sheets and spread out half a bag of fries onto each sheet. Bake the fries for 6 minutes. Then switch the trays from upper to lower and lower to upper, and turn each of them 90 degrees (flip back and front.) Bake an additional 6 minutes. If the fries aren’t quite crisp enough, bake them for 1-2 minutes more.
While the fries are cooking, organize the truffle oil, parmesan, and parsley. Then, make the aioli.
For the aioli: Whisk together the egg yolk, salt, and 1 tsp of malt vinegar. The yolk will get light colored and then darken a bit. Now is the time to start adding the oil. Whisking the egg mixture constantly, begin adding the oil in a slow, steady stream until all the oil is used and the sauce has thickened. Stir in the paprika. Then, taste the aioli and add more malt vinegar until you like the flavor. I find that one more teaspoon is perfect.
Once the fries are done, immediately toss them with 2 tablespoons of the truffle oil and about half the parmesan and parsley. Mound them up in your serving dish and then top with the remaining truffle oil, parmesan, and parsley. Serve with the malt vinegar aioli.