Goals from Raul Meireles, Branislav Ivanovic, Salomon Kalou and a Fernando Torres double gave the Blues the three points, and Villas-Boas said that his players did what they set out to do against the Belgian champions.
"I think it was a very, very good display by the team, very focused as we spoke before and this is decisive when you play a game like this," he told Sky Sports News.
"We felt confident from the beginning but we needed to stay focused and get the result straight away and this happened in the first 25 minutes.
"It was a good result and puts us in a good position going into the Genk game away. If we get ten points it will be very, very good."
Chelsea resume their Premier League duties on Saturday when they make the short trip to Queens Park Rangers.