Prep the Potatoes: Wash the potatoes well. You can peel them for a classic French fry or leave the skins on for a more rustic feel. Cut them into batons about 1cm thick. Try to keep them as uniform in size as possible to ensure they cook evenly.

Soak and Rinse: Place the cut potatoes into a large bowl and cover with cold water. Let them soak for at least 30 minutes, or up to a few hours in the fridge. This step is vital for removing surface starch. After soaking, drain the potatoes and rinse them thoroughly under cold running water.

Dry Completely: This is the most important step for both safety and texture. Spread the rinsed potatoes on a clean tea towel or several layers of kitchen paper. Pat them until they are completely and utterly dry. Any water will cause the hot oil to spit violently.

Set Up for Frying: Pour the oil into a large, deep, heavy-bottomed saucepan or a deep-fat fryer. You want the oil to be at least 5cm deep, but the pan should be no more than two-thirds full. Heat the oil to 160°C (140°C fan). I find that a digital thermometer is my best friend for this part, as it removes all the guesswork.

The First Fry (The Blanch): Carefully lower about a third of the potatoes into the hot oil using a slotted spoon. Don't overcrowd the pan. Fry for 5-7 minutes. They should be soft and cooked through but still very pale in colour. They should not be brown at all.

Cool Down: Remove the blanched fries from the oil with the slotted spoon and let them drain on a wire rack lined with kitchen paper. Let them cool for at least 15 minutes. You can even do this step a few hours ahead of time.

The Second Fry (The Crisp): Increase the oil temperature to 190°C (170°C fan). Once it's at temperature, carefully place the cooled, blanched fries back into the hot oil, again in batches. Fry for 2-4 minutes, or until they are a deep golden brown and wonderfully crisp.

Season and Serve: Immediately remove the fries from the oil, drain them briefly on the wire rack, and transfer them to a large bowl. Sprinkle generously with sea salt and toss to coat. Serve straight away while they are piping hot.