Bring the milk to a boil in a pan along with cardamoms and cinnamon. Add the cake crumble and the nuts (preserve some for garnishing). Simmer, stirring at intervals on a low flame.
When it is almost half reduced add the sugar and simmer till it is dissolved. Check for consistency. Put off the flame and add the rose water.
Keep aside to cool and then refrigerate. Serve chilled topped with chopped nuts and saffron strands.