For many across the UK, the humble roast potato is the undisputed star of a Sunday lunch or Christmas feast. Achieving that perfect combination of a shatteringly crisp exterior and a fluffy, soft centre is a culinary quest for countless home cooks. Now, a London-based chef has boldly claimed to have a simple, one-ingredient trick that will elevate your roasties to life-changing levels.
The Chef's Secret Weapon
Nathaniel Smith, the culinary expert behind The Grubworks Kitchen, shared his method for flawless roast potatoes in an Instagram video on 19 December 2025. While his technique includes several key steps for achieving the ultimate crispy shell, it's his final flourish that he insists unlocks a new world of flavour.
Smith begins with the classic preparation: peeling and chopping potatoes into even chunks before boiling them in salted water. His first pro-tip is to add chicken stock to the boiling water, allowing the spuds to absorb savoury notes from the start. After draining, he lets the potatoes steam dry for five to ten minutes to eliminate all surface moisture, a crucial step for maximum crispiness.
The Crucial Technique for Crispiness
He then roughens up the surfaces by shaking the potatoes in the colander, creating more edges that will become deliciously crunchy. In a departure from some methods, Smith then lets the potatoes cool completely while the oil heats up in a roasting tin in a preheated oven. He believes this stops the potatoes from cooling the oil down too much when they are added, ensuring a fierce, immediate sizzle for the best crust.
The potatoes are roasted in the hot fat for roughly an hour, being turned halfway through. It is in the final five minutes of cooking that Smith introduces his game-changing component.
The Life-Changing Final Touch
Just before serving, Nathaniel Smith adds several generous dollops of butter and fresh garlic directly to the roasting tray. He then tosses the nearly-cooked potatoes in this aromatic, melting mixture, ensuring every piece is gloriously coated. The butter instantly emulsifies with the hot roasting fats and potato starches, creating a rich, flavourful glaze that clings to each crispy ridge.
For those who aren't fans of garlic, the chef notes that using butter alone will still significantly elevate the dish. This simple addition of garlic butter transforms the potatoes from a mere side dish into the undisputed highlight of the plate, adding a luxurious depth of flavour that plain salt and oil cannot match.
How to Cook Perfect Roast Potatoes
If you want to replicate the full method, follow these steps for the ideal roast potatoes recipe:
- Preheat your oven to 220°C (Gas Mark 7).
- Peel potatoes and cut into even-sized chunks.
- Place in a pot of cold, salted water (add chicken stock if desired), bring to a simmer and par-boil for 8-10 minutes.
- Drain thoroughly in a colander and let steam dry for a few minutes. Shake the colander to roughen the edges.
- Heat a generous amount of oil or fat in a roasting tin in the oven until very hot.
- Add the potatoes, coat in the hot fat, and season well. Roast for 40-50 minutes, turning halfway.
- In the last 5 minutes, add knobs of butter and crushed garlic to the tray, toss to coat, and return to the oven.
- Serve immediately, perhaps with an extra sprinkle of sea salt.
With Christmas dinner just around the corner, this clever hack from a professional chef offers a guaranteed way to impress your guests and make your Sunday roast truly unforgettable. Sometimes, the simplest additions make the biggest difference.
