When cutting the potatoes, the aim is to end up with 8 equal-sized wedges from each. Cut the potatoes in half lengthways, then lengthways again to make quarters, then again to create wedges. For this last cut, I prefer to start from the skin side and cut at a 45° angle towards the inner point. But do whatever you find easiest.
Next, place the wedges in a large bowl and cover with warm (not boiling) water. Leave to soak for 10-15 minutes and preheat the oven to 200°C (390°F).
Once the potatoes have soaked for 10-15 minutes, drain away the water and set the potatoes aside on a board or plate lined with kitchen towel. Pat them dry with another few pieces of kitchen towel.
To the empty bowl, add the olive oil, Cajun seasoning, and salt. Mix well to combine the spices with the oil.
Once combined, add in the potato wedges and toss well. You could also use your hands or a spoon to mix the wedges – just make sure each wedge is evenly coated. Line a large baking sheet with greaseproof paper, drizzle with a little olive oil, and tip the contents of the bowl onto the baking sheet.
Space out the wedges evenly across the sheet, using a second sheet or pan if necessary. Tip over any residual oil and spices from the bowl and then place the wedges in the oven.
Bake for 25 minutes, before removing from the oven to carefully flip the wedges over. I like to use a flexible spatula for this, and the greaseproof paper should mean they come away fairly easily. If they're really sticking, carefully edge the spatula underneath and drizzle a little more oil under the newly flipped side.
Return to the oven and bake for another 20-30 minutes, or until golden and crispy on the outside and soft on the inside. Some may crisp up quicker than others – you can remove these and return the rest to the oven to continue cooking.
Once cooked, sprinkle with a little more salt and serve while hot. I also like to add some chopped fresh coriander or parsley, but this is optional.