Bring a pot of water to the boil.
Add rice and turmeric to pot of boiling water (brown rice needs a lot of water so make sure you have plenty in the pot).
Boil, uncovered, for 25-30 minutes, until grains are tender.
Drain well through a sieve.
Peel cucumber, if needed, cut in half lengthways and thinly slice.
Thinly slice bok choy.
Drain pineapple and roughly chop.
Combine cucumber, bok choy, pineapple, tamarind sauce, chopped peanuts and spinach in a bowl. Set aside for serving.
Pat chicken dry and dice 2cm.
Heat oil in a pan on medium-high heat.
Cook chicken and rendang paste for about 3 minutes, until fragrant and golden.
Add coconut milk, reduce heat to low-medium and simmer for about 8 minutes, until sauce is thick and coats the chicken.
Stir through fish sauce. Season lightly with salt and pepper.
Top rice with chicken and a sprinkle of chilli flakes.
Serve rojak salad on the side.
