Put the potatoes in a large saucepan and cover with water.
Bring to the boil and simmer for 10 minutes.
Drain into a colander and shake the potatoes to break up the edges.
Heat the oven to 180 FAN/190 C/375 F/Gas 5.
Put the oil in a deep sided roasting tin and heat for 10 minutes.
Add the potatoes and turn in the oil then roast for 30 minutes.
Turn the potatoes and roast for another 30 minutes.
Notes
The potatoes will take less time depending on their size. If the potatoes are colouring nicely after 20 minutes then turn them and roast for a further 20 minutes.The nutritional information in this recipe is provided by assuming that all of the ingredients are consumed, however much of the oil remains in the roasting tin. I have made an assumption that a tablespoon of oil is consumed for 4 servings which would be 129 calories per portion.