Half-fill a large pan with water. Add a large pinch of salt. Cover and put on a high heat to come to the boil. Preheat your oven to 180°C/Fan 160°C/Gas 4.

Scrub and peel the potatoes. Chop them into roughly equal-sized chunks, around 3-4cm across. Pop them in a large colander and rinse under cold water to get rid of some of the starch. When the water in the pan is boiling, add the potatoes. Bring back to a gentle simmer, and then simmer for 5 mins.

Drain the potatoes, then tip them back into the pan. Gently shake them to rough up the edges (this will help the potatoes crisp up in the oven). Lay a couple of clean tea towels out on your kitchen surface and tip the potatoes onto them. Spread the potatoes out and let them steam-dry for up to 10 mins (no longer than that or the potatoes will develop a ‘skin’ and become leathery).

Meanwhile, add 2 tbsp oil to a large roasting tin. Put them in the oven to heat the oil for 10 mins.

Take the roasting tin out of the oven. Add the potatoes and season with a pinch of salt. Turn them a few times to coat in the hot oil. Drop 1 bay leaf into the tin. Roast for 45 mins, turning the potatoes after 25 mins, till they’re golden brown.

Meanwhile, pick the rosemary and thyme leaves off their woody sprigs and finely chop them. Dice 50g of the butter.

After 45 mins, remove the tin from the oven. Drop in the butter and toss the potatoes to coat them in the butter. Scatter over the rosemary and thyme. Season with salt and pepper. Toss again to coat the potatoes in the herbs.

Return the potatoes to the oven for 5-10 mins till golden brown and crisp. Transfer to a dish and serve.