Peel the Yukon Gold potatoes and sweet potatoes, and cut them into thin, even-sized sticks.
Rinse the potato sticks under cold water to remove excess starch.
In a large pot or deep fryer, heat vegetable oil to 350°F (175°C).
Carefully add a batch of potato sticks into the hot oil and fry for about 5-6 minutes, or until golden brown and crispy.
Using a slotted spoon or tongs, transfer the fries to a paper towel-lined plate to drain excess oil.
Repeat the frying process with the remaining potato sticks.
Sprinkle the hot fries with salt to taste.
Instructions for Fish Sauce Aioli:
In a small bowl, combine mayonnaise, fish sauce, minced garlic, lemon juice, and Dijon mustard.
Whisk together until well combined and smooth.
Season with salt and pepper to taste.
Adjust the flavors by adding more fish sauce, lemon juice, or garlic according to your preference.
Serve the Pomme Frites hot with the Fish Sauce Aioli as a dipping sauce. The combination of crispy fries and tangy aioli will make a delicious and flavorful snack or side dish. Enjoy!