In your blender/mixer jar, take 1 cup yoghurt, ½ cup chilled water (or milk), cardamom powder, mango pulp and ice cubes - I have not added jaggery here as my mango pulp was quite sweet. Blend everything together until well incorporated
Check if you need to adjust for sweetness. Pour in individual tall glasses until half full
Wash your blender jar and add the remaining yoghurt, water (or milk), rose essence, food color (if using), jaggery powder and ice cubes. Blend everything until evenly mixed
Pour the rose lassi over the mango lassi in the glasses. Garnish with pistachios and rose petals and serve chilled. Enjoy!