1. Peel the potatoes, then cut into ribbon strips by peeling off the flesh in a spiral fashion, about 3 mm (1/8 in) thick.
2. Gradually heat the fat to a medium heat and fry the strips until they start to rise in the fat.
3. Remove and drain in a frying basket.
4. Bring the fat heat up again until hot and a blue haze can be seen.
5. Plunge the potato strips in and cook until golden brown and puffed up.
6. Drain on absorbent paper, sprinkle with salt and serve with drinks.