Resuming their second innings following on at the overnight position of 21 for one, the West Indies were dismissed for 231 in another abject batting display, despite half-centuries by Marlon Samuels and Carlos Brathwaite and a ninth-wicket stand of 95 between Brathwaite and Devendra Bishoo (45).
This result was India's largest margin of victory in a test match outside of Asia.
"We were really eager to get going in this series," said a delighted Indian captain Virat Kohli after the match.
"Everything came together nicely, from the batting performance to dismissing the West Indies twice. We went with three seamers because of the amount of grass on the wicket and it worked for us."
Wicketless throughout the first innings and for the first nine overs of his second innings effort, Ashwin scythed through the heart of the home side's batting in the afternoon session, reaping a five-wicket haul and then finishing off the match with the last two wickets just after tea to give India a 1-0 lead in the four-match series.
He was fortunate to claim his first wicket, opening batsman Rajendra Chandrika adjudged caught at the wicket for a painstaking 31 in over three hours at the crease.
But there was no doubt about the demolition effected thereafter, including dismissing Samuels for his first half-century in 12 test innings, as six wickets tumbled for 44 runs.
"Virat told me I needed to put in a good spell this afternoon and I'm glad I was able to deliver," said Ashwin, reflecting on his superb performance with the ball.
"I wasn't getting the right sort of rhythm yesterday but today was very different."
Such was the speed of the collapse that India looked on course to complete the win well before the tea interval.