Mix the onion, beetroot and chickpeas in a roasting tin with the garlic, ginger, chilli, spices, oil and salt, then transfer to the oven and roast for 40 minutes.
Give the coconut milk a good stir, then pour it over the beetroot and mix well. Return the roasting tin to the oven for 10 minutes.
Taste and season with more salt as needed and serve with rice or naan, scattered with fresh coriander and coconut flakes, if using.