Warm the oil in a large frying pan over a medium heat. Add the sliced onion and cook for 10 minutes or until lightly browned.
Increase the heat to high. Add the cubed aubergine, half of the sliced chilli, a tablespoon of tamarind and the muscovado sugar. Stir-fry for 5 minutes until the aubergine is golden and beginning to soften.
Add the cooked rice, mint, spinach and the remaining tamarind to the aubergine and onion mixture. Continue to stir-fry for 5—6 minutes or until piping hot.
Sprinkle over the remaining chilli slices. Season with salt and pepper and serve immediately.