Struggling to reach a mammoth victory target of 515, Bangladesh fought hard but were ultimately dismissed for 234, with skipper Najmul Hossain Shanto being the only player to provide some resistance with the bat.
Local star Ashwin was pick of the Indian bowlers, while his spin partner Ravindra Jadeja provided able support as the home side triumphed inside four days.
India captain Rohit Sharma heaped praise on his bowling attack for making the most of a red-soil pitch, which assisted both seamers and spinners.
"No matter what the conditions are, whether we play in India or outside, we want to build the team around that," he said.
"In the last few years, wherever we have travelled, wherever we played, we managed to have that in our armoury - whether it is seam bowling options or spin bowling options."
After Bangladesh resumed on 158-4, Shanto and all-rounder Shakib Al Hasan kept India at bay with their dogged resistance in the opening hour.
Home captain Rohit Sharma pressed Ashwin into service and he responded by breaking the partnership in his first over of the day.
The wily off-spinner lured Shakib forward and Yashasvi Jaiswal took a bat-pad catch at short leg to end the batter's knock of 25.
Jadeja had Litton Das caught in the slip and the match was effectively over when Shanto's wild swing against the left-arm spinner led to his dismissal.
Once their captain had left, a rudderless Bangladesh collapsed in a heap to lose the match with five sessions to spare.
Ashwin, who smashed a match-defining hundred in India's first innings, bagged player-of-the-match award.
Shanto said they wanted to extend the match despite being left with a mountain to climb in the contest.
"Just tried to bat as long as we can, we were not thinking about outcome," he said.
"Just try to follow our process and play with our strength. That's what we try to do."
The Bangladesh captain was pleased with his bowlers and said the batters must contribute more in the second and final test beginning in Kanpur on Friday.
"The bowlers did a great job. I hope the batters will do something special in next test match."
This article was generated from an automated news agency feed without modifications to text.
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