Can you recount the story of Cholkar and his vow to Sai Baba?

The story of Cholkar, detailed in Chapter 15, is a poignant example of Sai Baba's omniscience and compassion. Cholkar, a man from a poor household, vowed to distribute sugar candy in Baba's name if he passed a crucial job examination. Upon passing, financial difficulties, described as the 'threshold-ghat' of home expenses, delayed his pilgrimage to Shirdi. As a personal penance for this delay, he gave up eating sugar. When he finally made it to Shirdi and fulfilled his vow, Baba astonished him by telling his host, Jog, to give Cholkar 'cups of tea, well-filled with sugar.' This revealed that Baba was aware of Cholkar's secret vow and his private sacrifice, thereby cementing the devotee's faith.