Place the potatoes in a pan of cold water and bring to the boil, then let them cook for about 25 minutes, until you can easily stick a knife through them. Drain them well.
Place the potatoes in a large pan and add the garlic, turmeric, coriander, chilli, ginger, coconut milk, tomato purée and tomatoes. Bring to the boil, season with salt and pepper, then add the quinoa with a mug of just-boiled water (300ml).
Reduce the heat to a simmer, place the lid on and allow to cook. Over the next 30 minutes, stir every 5 minutes or so to make sure nothing sticks to the bottom. (This is quite a long cooking time, but this is how long quinoa takes to cook in all these ingredients, rather than just in water.) Halfway through cooking, add the chickpeas. When there are just 5 minutes left, add the spinach and stir it in until it wilts. Once the quinoa has cooked and is fluff y, not crunchy, it’s ready.