Batata harra

Heat the oven to 240C/465F/gas mark 9. Bring a saucepan of salted water to a boil, throw in the potatoes and cook for three minutes. Drain and leave in a colander until completely dry. Mix the potatoes with the oils, two teaspoons of salt and some black pepper, and spread on a medium roasting tray lined with tin foil; the potatoes should fit in snugly in one layer. Put them in the oven to roast and, after 10 minutes, stir in the garlic, pul biber, red pepper and half of the coriander. Return to the oven and roast for a further 25-30 minutes, until the potatoes are nicely coloured and completely tender. Stir once halfway through the cooking. Remove the potatoes from the oven and transfer to a large bowl. Stir in the lemon zest and juice, taste and add salt and pepper if needed. Serve warm or at room temperature, stirring in the remaining coriander at the last minute.