The Three Lions put six unanswered goals past the Bulgarians at their own backyard with braces from Raheem Sterling and Ross Barkley adding to Marcus Rashford and Harry Kane strikes.
The game was however marred by racist chants directed towards England players from the home crowd with the referee calling it to a halt on two occasions in the first half in order to have the issue addressed.
Balakov failed to condemn the racist chants after the game, claiming he did not hear them but found time to call England supporters to order for unacceptable behaviour throughout the game.
"I personally did not hear the chanting that you are most probably referring to. I saw that the referee stopped the game," Balakov told ITV.
"But I also have to say that the unacceptable behaviour was not only on behalf of the Bulgaria fans but also the English fans, who were whistling and shouting during the Bulgarian national anthem.
Henderson was seen conversing with Balakov during one of the breaks before half time and was incensed by his denial after the game.
"I had a few words with the manager. It wasn't acceptable – something needs to be done," the Liverpool captain told Sky Sports News.
"He needs to apologise now, really, on behalf of the team and the fans. He knows what was going on. He was asking me what the problem was.
"When I told him he knew what was going on, it was baffling how he didn't, really. Hopefully he looks back and apologises because anyone watching that game would be disgusted really."
