Jamie Oliver’s Freeze Ahead Roast Potatoes are parboiled potatoes that are lightly roughened, cooled, and frozen before roasting. Freezing dries the outer layer slightly, which helps create an extra crispy exterior when baked at high heat.
Peel the potatoes and cut them into evenly sized chunks. Try to keep the pieces similar in size for even cooking.
Place potatoes in a large pot of cold salted water. Bring to a boil and cook for 10–12 minutes until the edges start to soften but the centers remain firm.
Drain well and let them steam dry for 5 minutes. Gently shake the pot to rough up the edges. This creates texture that turns crispy later.
Spread the potatoes on a tray in a single layer. Allow them to cool fully at room temperature.
Place the tray in the freezer until potatoes are solid. Once frozen, transfer to freezer bags for storage. They can be kept frozen for up to 1 month.
Preheat oven to 200°C (180°C fan). Heat oil or fat in a roasting tray until hot. Add frozen potatoes directly to the hot oil. Roast for 40–50 minutes, turning halfway through, until golden and crispy.
Find it online: https://jamieolivereats.uk/freeze-ahead-roast-potatoes/