Rinse the basmati rice several times in cold water until the water runs clear. Soak the rice in fresh water for at least 2 hours, then drain well. This step ensures the grains soften evenly before cooking.

Transfer the soaked rice to a large heavy based pot and add the measured water. Bring to a gentle boil over medium heat, then reduce to a steady simmer. Stir occasionally and allow the rice to cook until the grains burst and the mixture becomes creamy.

While the rice cooks, grind the saffron threads with a pinch of sugar using a mortar. Add 2 tablespoons of hot water and set aside to release its colour and aroma, preparing it for the pudding.

Add the sugar to the softened rice and stir continuously for several minutes until fully dissolved. Keep the heat moderate to prevent sticking, then move smoothly into the next flavouring stage.

Pour the bloomed saffron and ground cardamom into the pot. Stir gently to distribute the colour evenly, watching the pudding turn a deep golden shade as it thickens further.

Add the slivered almonds and butter, stirring until the butter melts completely. This step adds richness and a subtle nutty texture, preparing the pudding for its final fragrance.

Stir in the rosewater and reduce the heat to low. Cook for a further 10 minutes, stirring frequently, until the pudding reaches a thick but flowing consistency.

Remove from the heat and allow the pudding to rest for 10 minutes. Spoon into shallow serving dishes, smoothing the surface gently before decorating.

Dust the surface with cinnamon and garnish with pistachios and almonds in traditional patterns. Serve warm or chilled, allowing the flavours to settle fully before eating.