Tip the rice into a large bowl and cover with cold water. Whisk for 1-2 mins till the water goes cloudy. Drain and rinse under cold water. Tip into a small pan. Add 400 ml boiling water and a pinch of salt. Cover. Bring the pan to the boil.
Turn the heat right down and gently simmer the rice for 25 mins till it is tender and the water is absorbed. Take off the heat. Set aside, lid on, for 5 mins to finish cooking the rice.
While the rice cooks, peel and finely chop the onion. Halve the squash and peel it. Scoop out the seeds and roughly chop. Peel and grate the garlic and ginger.
Warm ½ tbsp oil in a deep frying pan or wok over a medium heat. Fry the chicken for 8-10 mins till it’s browned all over, turning once or twice so it browns evenly.
Add the onion to the pan. Season well. Cook and stir for 3-4 mins till the onion has started to soften and has a little colour. Add the chopped squash, garlic and ginger. Cook and stir for 1 min till the pan smells aromatic.
Bash the cardamom pods with a pestle or rolling pin to open them up a little. Add them to the pan with 1 cinnamon stick. Pour in 200 ml boiling water and the coconut milk. Cover. Bring to the boil. Turn the heat down and simmer for 15 mins till the squash is tender.
Lift the cinnamon stick and any cardamom pods you can see out of the curry. Stir in the baby leaf spinach. Taste and adjust the seasoning. Serve the curry with the rice.