Can you recount the incident with the woman who came to Shirdi intending to fast?

Certainly. Chapter 32 tells the story of a woman named Mrs. Gokhale who came to Shirdi with a letter from Dada Kelkar. She had made a firm resolve in her mind to fast for three days while sitting at Sai Baba's feet. This was in direct opposition to Baba's own practice of never fasting. However, Baba, being the all-knowing inner witness, was already aware of her intention. He had previously remarked to Dada Kelkar, "will my children remain hungry? How can I let them remain so?" When Mrs. Gokhale arrived and went for darshan, Baba, who knows what is in everyone's heart, immediately gave her an instruction, preempting her plan to fast.