Peel potatoes and cut into chunks. Leave in a pan of well-salted water for several hours.
Drain, cover with fresh water but no salt.
Parboil til *just* tender - i.e. if you stick a skewer in, it goes in but there's still some resistance.
Drain, then clap lid on pan and give a good shake.
Season well with pepper and whatever else floats your boat.
Tip the potatoes into a roasting tray with a good half inch depth of smoking hot beef dripping and a few spoons of garlic oil.
Roast until crispy, turning regularly.
P.S. You do need a good floury potato for these.