Can you tell me the story of Boss Dharamsee and the grapes? I've heard it's a famous miracle.

Certainly. The story of Boss Dharamsee, detailed in Chapter 35, illustrates Baba's omniscience and grace. Dharamsee arrived in Shirdi with a skeptical, 'clinical' mindset. When Baba began distributing grapes with seeds, Dharamsee was internally conflicted as he disliked them and his doctor had forbidden unwashed fruit. He even questioned Baba's sainthood in his mind for forcing them upon him. In response, Baba gave him more and instructed him to eat them. Upon obeying, Dharamsee was astonished to find the grapes were perfectly seedless. This miracle shattered his ego, replacing his skepticism with love and devotion for Sai, and he resolved to return to Shirdi.