Preheat and Prepare: Preheat your oven to 220°C (200°C fan). Line two large baking trays with baking parchment. Using two trays is important to avoid overcrowding.

Cut the Fries: Wash and scrub the sweet potatoes well. I find that leaving the skin on adds a lovely texture and extra nutrients, but you can peel them if you prefer. Cut them into uniform batons, about 1cm thick. Try to keep them a similar size so they cook evenly.

Soak the Potatoes (Optional but Recommended): Place the cut fries in a large bowl and cover with cold water. Let them soak for at least 30 minutes. This step helps to draw out excess starch, which contributes to a crispier finish.

Dry Thoroughly: Drain the water and dry the sweet potato batons completely. Spread them on a clean tea towel and pat them dry. This is the most critical step for crispiness!

Mix the Coating: In a small bowl, whisk together the cornflour, smoked paprika, garlic powder, onion powder, fine sea salt, and black pepper.

Coat the Fries: Place the dry fries in a large, dry bowl. Drizzle with the olive oil and toss well until every fry is lightly coated. Then, sprinkle over the cornflour and spice mixture. Toss again until the fries are evenly dusted with the seasoning.

Arrange on Trays: Spread the seasoned fries in a single layer across the two prepared baking trays. Make sure there is space between each fry. If they are too close together, they will steam rather than roast.

Bake to Perfection: Place the trays in the preheated oven and bake for 15-20 minutes. Then, remove the trays, carefully flip the fries over with a spatula, and return to the oven for another 10-15 minutes, or until they are golden brown and crispy at the edges.

Serve Immediately: Transfer the hot fries to a serving platter, sprinkle generously with flaky sea salt and the optional chopped parsley. Serve them straight away while they are at their crispiest.