Preheat the oven to 200ºC/fan 180ºC/gas mark 6. Put the wedges in a pan, cover with cold water and bring to the boil. Cook for 3 minutes, then drain.
When the wedges have cooled a little, put them in a large bowl. Season and toss with the olive oil and chilli powder.
Put the wedges skin-side down on a baking tray and bake for 30 minutes, shaking every so often to stop them sticking.