To make Spice paste: soak the chillies in hot water for 30 minutes or until soft; drain. Place the softened chilies and salt in a food processor and process until a smooth paste is formed. Add all the other paste ingredients one at a time while continuing to run the processor.
Combine the coconut cream, brown sugar, fish sauce in a large bowl. Add the spice paste and stir together until well combined.
Stir in the chicken strips.
Select a round heatproof serving dish which will fit into a large, deep pan. Put the spinach onto the serving dish. Spoon the spicy chicken mixture over the spinach.
Place a saucer or rack on the base of the pan and pour enough boing water to cover it. Place the dish on top of the saucer or each, cover the pan with a tight fitting lid and steam over medium heat for about 30 minutes or until the chicken is cooked.
Check from time to time that there is enough water in the pan.