Peel and cut the potatoes into 2 or 3 depending on how large the potatoes are. You want the potato chunks to be roughly similar sizes(check out the diagram for the optimal cutting pattern)
Par boil the potatoes in salted water. Don't cook all the way through as they might disintegrate.
Get a large roasting dish ready with a decent layer of oil in the tray. Put into a moderate oven (180c/Gas Mark 6) to heat the oil.
Drain the potatoes & return them to the hot pan very briefly to steam off any of the water.
Bash the potatoes around & sprinkle with semolina flour (if you're using it) to give a nice rough edge to create the all important crunchy bits! Sprinkle over some salt.
Carefully add the potatoes to the prepared hot oil in the baking tin, toss to cover in the oil & put back in the oven for at least 20 mins.
Finely chop the herbs.
Check on the potatoes, giving them another good shake around in their pan to ensure even cooking. The potatoes will be nearly cooked now, so sprinkle over half the chopped herbs.
Give the potatoes another 5-10 mins in the oven - or until they are golden brown and crunchy.
Sprinkle over the rest of the herbs while still in the pan & season to taste. Serve now, or you can leave in a low oven ready to serve when everything else in your feast is ready!