If You Want Crispy Roast Potatoes, Avoid This Common Mistake

Failing to do this crucial step can make your spuds less crispy.
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People, I have been humbled by roast potato facts recently.

I thought my recipe was foolproof until I realised that not only should I be adding Mary Berry-approved semolina to the veggies for an extra crunch, but I should also retire my extra-virgin olive oil additions.

And now, it seems I’ve been making another mistake on my way to crispy, fluffy perfection ― turns out it’s important to cool your parboiled potatoes before cooking them.


According to Marc Williams, cookery school director at The Grand in York, it’s all to do with moisture.

We’ve written before about how applying low-moisture semolina to the outside of potatoes can ensure they crisp up as they cook rather than steaming their skins to softness.

Well, the same philosophy applies here. When you parboil your roast potatoes, you infuse them with water (no shockers there). And the steam puffs out from the exterior of your potatoes for a while after removing them from the water.

This can interfere with the potatoes’ interaction with the hot oil you should be adding them to after roughing up their sides and adding seasoning. And if they’re seriously steamy, or even wet, you can get some dangerous splashback.

You should “strain them and wait until the steam stops,” William shared. “You’ll never get a crisp result if they are full of water.”

In fact, Joe White, head chef at 10 Tib Lane in Manchester, even goes so far as to say “For the perfect roasties make sure to steam or boil them the day before and let them air dry overnight in the fridge. It will make the outside extra crispy when you roast them.”

What’s the right method, then?

According to Williams, “To get the perfect potatoes, peel them, add to cold water and bring to boil. Boil for around six minutes until the edges soften.”

Shake them in the colander while hot to provide rough, textured edges, and apply semolina and seasonings while the spuds are still hot. Freshly-boiled potatoes will provide fluffier outer layers, and ingredients stick better to hot food.

Then, strain them and cool them. When you’re ready to cook them, place a fat of your choice ― duck fat if you want to be luxurious, though sunflower and vegetable oils are great options ― in a baking tray to get hot before adding the spuds.

“Roast for around twenty minutes in a hot oven before turning them over; this allows a crust to form underneath, so you won’t leave half the potato stuck to the tray,” Williams recommends.

Bon appetit!