Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3). Wash potatoes thoroughly, dab dry and peel if necessary.
Cut the potatoes lengthwise into slices and spread evenly on a baking tray. Mix olive oil with salt, pepper and chilli. Drizzle potatoes with it. Bake in a hot oven for 35-45 minutes until golden brown, turning frequently.