World champions India, having rested several first-choice players, bowled out Bangladesh for 127 and returned to chase down the target in 11.5 overs to grab a 1-0 lead in the three-match series on Sunday.
Put in to bat in the series opener in Gwalior, Bangladesh lost both openers early after India's left-arm seamer Arshdeep Singh (3-14) struck twice in his first seven balls.
Touring captain Najmul Hossain Shanto made 27 and Mehidy Hasan Miraz 35 not out, but Indian spinner Varun Chakravarthy (3-31) wrecked their middle order.
India lost opener Abhishek Sharma (16) in the second over but Sanju Samson and skipper Suryakumar Yadav chipped in with breezy knocks, both scoring 29, as the hosts breached the 50-mark in the fifth over.
Debutant Nitish Kumar Reddy remained unbeaten on 16 and watched from the other end as Pandya finished the game in style by hitting Taskin Ahmed for three successive boundaries in the 12th over.
With India needing 10, Pandya played a no-look ramp shot that raced to the rope, followed it with a slashed four during which his bat flew towards square leg and then sealed victory with a pulled six.
India had swept Bangladesh in the preceding two-Test series.
Delhi and Hyderabad host the remaining two matches of the series on Wednesday and Saturday respectively.