Chef Poppy O'Toole has shared the one vital step home cooks should not skip to achieve the ultimate crunch on roast potatoes: letting them steam dry for around 10 minutes after boiling.
In a recent TikTok video, O'Toole listed her top 10 rules for making the best roasties at home. She explained that while boiling the potatoes, they should be cooked for a little longer than usual — between 10 and 15 minutes. The next step, however, is crucial for getting a crispy and crunchy shell on the outside.
The steam drying method
O'Toole said: “Rule number seven: always steam dry your potatoes. Now, once you’ve drained your potatoes into a colander, use a pan that you had previously, put them over the top and then put it back onto the hob where you were just boiling your potatoes, but turn it off.”
She added: “The residual heat and any water that’s left in there is gonna steam up, and it’s gonna help dry your potatoes out.” After placing a tea towel over the top, the potatoes should be left to steam dry for around 10 minutes.
Why it makes potatoes crispier
O'Toole continued: “The drier your potatoes when they go into the oven, the crispier they’re going to be.” Wet potatoes steam themselves in the oven instead of frying or roasting, which leads to a soggy or pale crust. Steam drying allows surface water to escape into the air, making a better surface for hot oil to cling to.
Eliminating water allows hot oil or fat to immediately make direct contact with the potato surface upon entry into the oven, triggering a fast, even sear. Removing moisture helps the outer layer dry out and turn crunchy, while keeping the centre light and fluffy.
Roasting and extra crispiness
Once the potatoes are dried, they should be added to hot oil or fat and coated. Roast in the oven at 200°C (fan) for 30 minutes, then remove the tray and turn the potatoes once. Return to the oven and roast for another 20 to 30 minutes. O'Toole said: “Hmm. Perfect, every time.”
For a craggier edge and little crispy bits, the potatoes can also be chuffed before being put in the hot oil — simply shake them in the saucepan or container before allowing them to steam dry. This breaks down the edges and allows them to crisp up when roasted. O'Toole previously described this step as the “most important” to achieve crispy roast potatoes to BBC Food.
