Preheat the oven to Gas Mark 6, 200°C, fan 180°C. Peel the potatoes and cut them in half lengthways to maximise their crispness. Place in a large pan of boiling water, bring back to the boil, then cook for 5 minutes.
Drain and place in a large bowl. Season with the oil, rosemary, and pepper. Cover with a lid and shake to combine. The potatoes can be roasted straightaway, or stored in the fridge and used later or even the next day.
To roast, heat the oil in a roasting pan and add the potatoes, turning to ensure they are evenly coated in oil. Add a very small amount more oil only if potatoes have been stored and soak it all up. Roast for 45 minutes to an hour, turning once before serving. If you like, add another sprig of fresh rosemary on top to decorate.
For richer-tasting roasties, use goose fat. Ensure the fat is piping hot before adding the potatoes to the tin
For a tasty twist to roast potatoes, add 2 tablespoons coarse semolina and 1 teaspoon smoked paprika to the drained potatoes before roasting until crisp.
See more Sunday Roast recipes
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