The Zoroastrians of Persia (modern-day Iran) fled to avoid forceful conversion by the Islamic invaders and landed in Sanjan, a port in Gujarat by sea (Valsad, present day name). This was following the fall of the Sassanid Empire, to seek refuge in India.
Because of the language barrier, King Jadi Rana, the then ruler of Sanjan, brought out a glass full to the brim with milk to explain that there were too many people in his land already. The Zoroastrian priests then promptly added a spoonful of sugar into the milk to show how easily they would blend in among them and also sweeten the land, helping it prosper with their presence.
Jadi Rana gave was so impressed with this gesture that he granted them asylum and welcomed them with gifts and helped them settle in the new land of India. Parsis thus settled and assimilated, blended in India like sugar in the milk.
Painting: Dadar Parsi Colony by Pratyashi Bordoloi, a convservation architect and urban sketcher