Tip the rice into a bowl. Cover with cold water and whisk for 1-2 mins (you can use a fork) till the water goes cloudy (this is the starch). Drain, rinse the rice under cold water. Tip back into the bowl. Cover with fresh water. Set aside.
Peel and thinly slice the garlic and ginger. Halve the chilli and flick out most of the seeds. Finely chop it.
Pour the coconut milk into a large pan. Add 300ml water. Add the garlic, ginger and chilli. Sprinkle in the turmeric. Add a large pinch of salt. Place the pan on a gentle heat and bring to a simmer. When the golden coconut broth is bubbling, carefully lower in the chicken breasts. Cover with the pan lid and lower the heat. Poach the chicken for 15 mins.
While the chicken is cooking, drain the rice and tip into a small pan. Add 400ml boiling water and a pinch of salt. Cover. Bring to the boil, then turn down the heat. Simmer for 8 mins till all the water is absorbed and the rice is tender. Take off the heat. Set aside, lid on, for 4 mins to finish cooking the rice.
While the rice cooks, trim and peel the carrot. Cut it in half lengthways, then into thin strips. Finely shred the pak choi.
Lift the chicken out of the turmeric broth and pop on a plate. Insert a sharp knife into the thickest part of the breast and check that it's cooked through. There should be no pink meat or juices. Cook a little longer if there are. Cover the plate with foil and set aside to rest.
Increase the heat under the broth and bubble for 3 mins to reduce it slightly. Drop in the carrot and pak choi. Cook for 2 mins so they're just tender but still with some bite.
Spoon the rice into warm bowls. Top with the veg. Thinly slice the chicken breasts and arrange on top of the rice. Ladle over the turmeric and coconut broth to serve.