Armenian Sweet Barley Pudding (anoushabour)

Rinse barley under cold running water, then place in a saucepan with sugar, sultanas, spices and enough water to just cover barley.
Bring to the boil, stirring occasionally, then reduce heat to low and cook for 2½ hours, adding ½ cup water every 30 minutes or until barley is soft. Discard cinnamon stick. Blend using a handheld blender until a porridge-like consistency; the high sugar content means it is likely to burn easily, so keep topping up with more water and stirring occasionally, if needed.
Remove from heat, then pour pudding into a shallow dish. Sprinkle with cinnamon, and decorate with pistachios, walnuts and almonds. Refrigerate until cold before serving.