After posting about how I made my roast potatoes, I cooked them again.
One of the key processes is the par-boiling which softens the potatoes and ensures they get really crispy.
For me the other key processes are leaving them drained par-boiled potatoes to dry before placing them in a hot roasting pan with hot oil. I know that some swear by goose or duck fat, and I do quite like that, but recently I have just been using a bit of sunflower oil and olive oil for flavour.
Other times I have added flavourings to my roast potatoes, this has included rosemary, onion, garlic, pancetta or a combination.