After a goalless first half, Hazard broke the deadlock 11 minutes into the second period with a low drive beyond Allan McGregor, who had an otherwise impressive game in Hull's goal.
Torres then got the better of Alex Bruce three minutes from time to burst into the danger area and slide the ball beyond the Scottish goalkeeper to make sure of the points.
The win is Chelsea’s fifth in a row in all competitions and, with Manchester City and Arsenal not playing until Sunday and Monday respectively, sees them sit atop the English top flight.
Steve Bruce made just a single change to the side that lost 2-0 to Liverpool last time out in the Premier League, George Boyd coming in for captain Robert Koren, While Jose Mourinho gave Oscar and Willian starts after starring substitute outings at Southampton on New Year's Day.
Ahmed Elmohamady had the first chance of the match for Hull in the seventh minute, with Petr Cech getting down well to gather the Egyptian’s dipping effort from 25 yards.
It was the hosts who had the better chances throughout the opening half hour with Cech into action once again in the 22nd minute, pushing the ball around his left-hand post from a 20-yard Jake Livermore strike, while Yannick Sagbo wasted a gilt-edged chance after George Boyd charged down an attempted John Terry pass in the Chelsea penalty area.
Chelsea worked their way back into the contest and Oscar squandered a glorious opportunity to break the deadlock for the visitors in the 33rd minute, drawing a superb save from McGregor after receiving the ball somewhat fortuitously from a deflected Hazard cutback.
And Scotland international McGregor had to be alert again on the stroke of half-time as a well-struck Luiz free-kick required a touch over the crossbar, before a second set-piece from the Brazilian after the break was again stopped by the 31-year-old.
But it was Hazard who eventually netted the first goal of the match in the 56th minute, delaying his shot on the edge of the penalty area before rifling an effort into the bottom right-hand corner for his ninth Premier League goal of the season, equalling his tally from last term.
With hull struggling to find a response, Torres extinguished their hopes of salvaging a point in the 87th minute, taking the ball beyond Bruce to slot the ball into the bottom right-hand corner, scoring in consecutive Premier League games for the first time since December 2012.
And Chelsea cruised to the full-time whistle to secure their fourth clean sheet in five outings - taking Cech past Peter Bonetti's club record.
