Rangers stretched their club-record unbeaten start to the season to 18 games, and leapfrogged Cardiff into the bargain, courtesy of Rob Hulse's early goal and Taarabt's superb second-half double.
The talented midfielder is spearheading Rangers' promotion charge and has now scored eight goals since joining on a permanent basis from Tottenham
Preston, by contrast, were condemned to a fourth defeat in five games despite a late own-goal from Matt Connolly, to heap more pressure on Darren Ferguson.
Not even a helping hand from his dad Sir Alex Ferguson, who this week loaned him young Manchester United full-back Ritchie De Laet, could lift the gloom for the embattled North End boss.
Instead, Ferguson Junior's afternoon got off to the worst possible start when Kyle Walker whipped in a cross which should have been comfortably dealt with by Andy Lonergan.
However, the visiting keeper allowed the ball to slip through his fingers and gifted Hulse a tap-in for his first goal since joining Rangers from Derby on deadline day.
With Preston looking shaky, the hosts had plenty of chances to double their lead in the first half with Kaspars Gorkss heading Taarabt's corner wide and Jamie Mackie's volley flying the wrong side of the post.
Lonergan partially redeemed himself when he saved with his feet from Mackie and Leon Clarke fired over the crossbar.
Clarke also had a goal disallowed for a handball before Preston finally managed a shot on target, Paddy Kenny easily dealing with Michael Tonge's long-range effort shortly before the break.
The crucial second goal did not come until after the interval, but it was well worth the wait.
Taarabt collected the ball some 25 yards out, cut inside onto his right foot and dispatched a stunning curler past Lonergan and into the net.
Hulse could have doubled his tally just after the hour but he was twice denied on the goal-line by Jon Parkin and Lonergan as Preston struggled to deal with another Taarabt corner.
Taarabt was also sniffing about for his second but Lonergan did well to spread himself as the Hoops skipper burst through.
However, the mercurial Moroccan was not to be denied and with six minutes left he unleashed a bullet of a drive which deceived Lonergan and flew into the back of the net.
Preston's travelling fans were at least given something to cheer with three minutes left when Connolly turned Iain Hume's cross into his own net.