Can you tell me the story about Mrs. Gokhale and her decision to fast in Shirdi?

Certainly. Chapter 32 recounts the story of a woman named Mrs. Gokhale who came to Shirdi for Sai Baba's darshan. She had brought a letter from Dada Kelkar and had made a firm resolution in her mind to fast for three days at Baba's feet. This intention was in direct opposition to Baba's teachings against fasting. Being the 'inner witness,' Baba was already aware of her plan. He had even told Dada Kelkar previously that he would not let his 'children remain hungry.' When Mrs. Gokhale arrived and had her darshan, Baba, knowing her resolve, gave her an instruction, reinforcing his principle that finding God on an empty stomach is unimaginable and that one must eat to find peace.