1. Wash and dry the potatoes. Cut into quarters, then in half, to make long thick fries.
2. In a large pan, heat the oil. Add the potatoes and fry for a few minutes on each side. (Use a deep fryer if you have one.)
3. Remove the fried potatoes from the oil and place on paper towels. Season with salt and pepper. Set aside.
4. In a bowl, mix together the mayonnaise, sour cream, chives, and lemon zest.
5. Serve the fries with the sauce.