- Heat your oven to 200℃ fan or 220℃ normal. Put a roasting tin in the oven and heat it for a few minutes.
- Add the oil, potatoes, garlic cloves, ½ teaspoon salt and a few grinds of black pepper to a bowl and toss well to coat the potatoes evenly. Scatter the sprigs of herbs around the potatoes and roast for about 35 minutes, shaking the tin a couple of times, until the potatoes are crisp and tender.
- After 35 minutes, add the butter, shake the roasting tin to coat the potatoes all over, then return to the oven for 5 minutes (give the roasting tin a shake halfway through to really get the butter all over them). Remove the roasting tin from the oven, transfer the potatoes to a serving plate (discard the garlic and herb stalks) and sprinkle over a little Maldon sea salt before serving hot.
These can be made ahead, refrigerated, and then reheated in a hot oven for a few minutes to heat them through.