Can you narrate the story of Cholkar's vow to Sai Baba and how it was fulfilled?

The story of Cholkar, as told in Chapter 15, begins with his financial struggles. To secure his job, he needed to pass an examination and vowed to Sai Baba that if he passed, he would distribute sugar candy (khadisakhar) in Baba's name. His wish was granted, but due to household expenses, described as a difficult 'threshold-ghat' to cross, he was delayed in fulfilling his vow. As a personal penance for this delay, Cholkar gave up sugar entirely. Eventually, he managed to travel to Shirdi, where he fulfilled his vow by distributing sugar and offering a coconut. The story culminates in Baba demonstrating his omniscience by telling another devotee to serve Cholkar tea 'well-filled with sugar,' proving that Baba was aware of his secret sacrifice all along.