4 large chipping potatoes, such as Yukon Gold, Spunta or Maris Piper, peeled
Vegetable or corn oil, for deep-frying
10 garlic cloves, peeled and thinly sliced
Using a mandolin with a shredding attachment or a sharp knife, cut the potatoes into long matchsticks, about 3mm thick. Wash them well in a couple of changes of cold water to remove the excess starch, then drain and pat dry on some kitchen paper.
Heat an 8cm-depth of oil in a deep-fat fryer or deep, heavy pan to 120-140C. Deep-fry the potatoes in manageable batches (a couple of handfuls at a time) for 2-3 minutes, then remove with a slotted spoon and drain in a colander.
Increase the temperature of the oil to 160-180C and re-fry the potatoes with the garlic slices in batches, moving them around in the pan, until golden and crisp. Remove with a slotted spoon and drain on kitchen paper. Sprinkle with sea salt and serve immediately.
Alternatively, you can keep the straw potatoes warm, uncovered, on a baking tray in a low oven until ready to serve. They should stay crisp but, if not, you can briefly re-fry them in hot oil.