The day before, tip the potatoes into a large pan of salted water and simmer for 10 mins or until just tender. Drain the potatoes in a colander, reserving a little of the cooking water, and leave to cool.

Now here’s the trick: choose the two chunks that are the most cooked and ready for mashing and push these through a potato ricer, then add a little of the cooking water to make a thick potato batter. Roll the cooled potatoes through the batter, then put on a tray lined with baking parchment and chill overnight.

The next day, heat the oven to 200C/180C fan/gas 6. Take a large roasting tin and add a good splash of vegetable oil. Place in the oven and heat for a few minutes, then carefully add the potatoes to the hot fat and turn to coat. Lightly season with salt and roast, without turning, for 40 mins.

Carefully turn over the potatoes and increase the heat to 220C/200C fan/gas 8. Continue to roast for a further 20 mins, turning again once, until beautifully crisp and golden all over.