Can you recount the story of the Yoga practitioner who visited Sai Baba with Nanasaheb Chandorkar as told in Chapter 23?

Certainly. Chapter 23 narrates the story of a practitioner of Yoga who, despite having thoroughly studied the Yoga Shastras, could not achieve Samadhi. Hoping the 'King of Yogis' Sai Baba could help, he visited the Masjid with Nanasaheb Chandorkar. However, his faith was shaken when he saw Baba eating stale bread with raw onions, and he began to doubt Baba's ability to help him. As the chapter explains, the omniscient Sai Maharaj perceived this doubt and remarked to Nana, "only those whose digestion is strong should eat onion." This statement startled the Yogi, who realized his doubt had been exposed. He then surrendered to Baba with true devotion, his doubts were resolved, and he left with a happy mind after receiving Udi and blessings.