Boil the potatoes in salted water with baking soda until just tender. Let them cool a little, then cut into large chunks.
Toss the potatoes with oil and spices, and the chickpeas with oil, cumin and salt. Roast together at 200°C for 25–30 min until crispy.
Meanwhile, stir the yoghurt base together.
Toss the hot potatoes with lime juice, zest, chilli oil and coriander.
Spread the yoghurt on a plate, pile the potatoes and chickpeas on top, and finish with the toppings.
