Preheat the oven to 200ºC, fan 180ºC, gas 6. Put the wedges in a pan, cover with cold water and bring to the boil. Cook for 3 minutes. Drain.
When the wedges have cooled a little, put them in a large bowl and toss with the olive oil and chilli powder, and season with freshly ground black pepper.
Put skin-side down on a baking tray and bake for 30 minutes, shaking every so often to stop them sticking. Serve with the soured cream and chive dip.