Healthier harissa-spiced potato bake

1 Put the potato slices in a large pan and cover with water. Bring to the boil, then reduce the heat and simmer for 5 min or until the potatoes are slightly tender. Drain.

2 Meanwhile, heat the sunflower oil in a non-stick frying pan, then add the onion and cook for 5–6 min until softened. Add the harissa paste and cook for a further 1–2 min.

3 Grease a large ovenproof dish with spray oil. Arrange a third of the potato slices in the dish, then top with a third of the onion mixture and a third of the chopped coriander. Repeat with the remaining potato slices, onion and coriander to create two more layers.

4 Put the evaporated milk in a saucepan and heat through. Pour the milk over the potato bake, then leave to stand for at least 30 min. Heat the oven to 190ºC/fan 170°C/gas 5.

5 Spray the top of the bake with oil and cover loosely with foil. Bake for 40–45 min until golden. Serve garnished with the extra coriander.