Cut the potatoes into chips about 5mm thick. Place them in cold water for 5 minutes to remove excess starch then drain well and pat dry with paper towel.
Half fill a deep fryer or large deep saucepan with oil and heat to 195 degrees C. Blanch the chips in the hot oil in two batches. This takes 4 to 5 minutes and when done they should be a very pale golden. Remove from the oil, drain well on paper towels and set aside for a minimum of 15 minutes.
When ready to serve re-fry the chips for about 2 minutes until crisp and golden. Drain well on paper towels and season with salt. Serve immediately.