Wash the potatoes thoroughly to remove all the grit.
Parboil the potatoes in a pressure cooker with lots of salt. The water should be salty like seawater as this will add flavour to the potatoes. Pressure-cook them for half the time than you would normally since we want half-done potatoes. To check, run a sharp knife through a potato - it should not go through easily. That is exactly how we need them for this recipe.
Preheat the oven to 200 degrees Celsius. Slide the rack into the second from top slot, closer to the upper grill.
Now transfer the potatoes from the cooker into a colander. Let them cool a bit and when easy to handle, peel and cut them into thin slices or cubes.
Season the potatoes with 2 tablespoons of oil, salt and pepper.
Cover the baking tray with foil and grease it. Arrange the potatoes over it and bake for 15 mins. or more till golden brown. Turn them and bake again for 15 mins. Serve hot.