For deep-frying:vegetable oil1.2 kgsebago potatoes, peeled, cut into 1cm-thick chips, soaked overnight in cold water, then drained
Heat oil in a deep-fryer or large saucepan to 120C. Cook chips, in batches, for 5 minutes or until cooked through, but not coloured. Drain and cool to room temperature. Increase temperature to 180C and deep-fry chips, in batches, for 3 minutes or until crisp and golden. Drain on absorbent paper, season to taste with sea salt and serve.