1.2 kg(about 6) floury potatoes, such as kestrel or King Edward, scrubbed1½ tspcoriander seeds¼ tspcumin seeds½ tspground turmeric½ tspchilli flakes80 ml(1/3 cup) extra-virgin olive oil
Preheat oven to 200C. Simmer potatoes whole in a large saucepan of salted water until tender (25-30 minutes). Drain, cool and peel, then cut into rough 4cm-5cm chunks.
Dry-roast coriander and cumin seeds until fragrant. Cool briefly, then finely grind in a spice grinder or with a mortar and pestle. Add turmeric and chilli flakes, transfer to a roasting pan along with olive oil and potatoes and toss to coat, season to taste and roast, turning occasionally, until potatoes are crunchy on the outside (35-40 minutes). Serve hot with duck.