Villas-Boas' side maintained their one-point lead at the top of Group E with the thrashing in London, which came courtesy of goals from Raul Meireles, Salomon Kalou, Branislav Ivanovic, and a brace from Torres.
Torres put in a confident display, pestering the poor Genk defence throughout and came away with two goals - an 11th-minute strike and a 27th-minute header - for his efforts.
The Spaniard's contribution was even more impressive given that he had not played for the Blues for three weeks due to a three-match suspension after being sent off against Swansea.
His manager decided to downplay the former Liverpool man's display, however, saying: "It's about the team's performance.
"Fernando played very well - but we look at the collective performance. I'm pretty pleased with the way the team played.
"It would have been a long period off (if Torres had not played), though we are able to choose from the best up front.
"The choice fell with Fernando today and he responded pretty well, as have all the strikers who have been used recently."
The young Portuguese boss did, however, stress that he never had any doubt that Torres would perform despite his recent absence from first-team action.
"It was never a question of him (not being in his best form)," Villas-Boas said.
"It's important for players to feel confident, and he's feeling confident in his abilities. He was always on form."
Villas-Boas rung the changes for tonight's game, giving Didier Drogba and John Terry a rest, but the Blues boss could probably have changed his entire team and still overseen an easy win against an ill-disciplined Genk team ravaged by a defensive injury crisis.
Torres' brace made it 3-0 after Meireles had bagged his first Chelsea goal when the Genk defence backed off, allowing the Portuguese to steady himself before unleashing a 25-yard effort that Laszlo Koteles did not even attempt to save.
More poor marking followed to allow Ivanovic to nod home almost unchallenged before the break and substitute Kalou lashed home to make it 5-0 on the rebound after Koteles had denied Torres a hat-trick with a point-blank save.
Villas-Boas, who has seen his side score 13 times in their last three matches, was happy to come through a match that he feels could have been a potential banana skin.
"To score two goals in the first 15 minutes, this put us in a very comfortable position," he said.
"It was a good display from everybody. I'm very happy with the performance, not only the way we played but the commitment of the team.
"This was a game that everyone expected us to win, and that's when surprises lie just round the corner. But we had the focus and put in a good performance."
Another three points in Belgium next month would all but guarantee the club's qualification, but Villas-Boas is not getting carried away with talk of his team challenging for the Champions League trophy that Blues owner Roman Abramovich craves.
Villas-Boas said: "With seven points, we go to Genk and the three over there would put us in a good position to qualify but this group could become very tight depending on what happens in Leverkusen with Valencia.
"The most important months for us will be the last three of the season, when you finally win or don't win trophies.
"For now, we're just aiming at our objectives. We want the best results as possible to get qualification through, and keep on track for going as far as we can in the competition."
Genk boss Mario Been admitted Chelsea were a class apart from what his team could offer.
"They were on totally another level," Been said.
"We gave them the goals too easily. We needed to keep a clean sheet for the first 20 minutes, but we were two down after 10 minutes."