Traditional double-cooked French bistro frites: hand-cut floury potatoes blanched in beef tallow or peanut oil until tender, then flash-fried until shatteringly crisp and salted with fleur de sel.
Soak cut potato batons in cold water for 30 minutes to remove excess starch. Drain and dry completely in clean kitchen towels.
Heat oil to 150°C. Fry potatoes in batches for 5-6 minutes until soft and pale, without coloring. Drain on paper towels and cool completely.
Raise oil temperature to 190°C. Flash fry the blanched frites for 2-3 minutes until deep golden-brown and ultra crispy.
Transfer immediately to a bowl, toss vigorously with fleur de sel, and serve piping hot.