Steven Smith's shot from distance and Dean Shiels' clever finish had the visitors two goals ahead at half-time.
Robbie Duncan was sent off for the hosts after the break, with Lee McCulloch scoring the resulting penalty before Nicky Law sealed the win with a fabulous strike.
Stenhousemuir came into the game on an impressive run of 12 League One games unbeaten - a sequence that included a 3-3 draw at Ibrox in February - and showed they were a team playing with confidence by creating the first major opportunity of the match.
Sean Dickson forced his way into the box and squared for Ben Greenhalgh but the forward could only prod a tame effort straight at Cammy Bell, who was returning to the visitors' goal after two games out with a concussion.
Rangers' first attempt arrived when Fraser Aird won a free-kick a yard outside the box after drawing a foul from Bryan Hodge. Smith stepped up and struck a left-footed effort inches over the crossbar.
The visitors should have been ahead moments later when the lively Smith found space down the left and crossed for Jon Daly. The striker sliced his shot but the ball fell invitingly for Richard Foster, who fired wide of the near post when he seemed destined to score.
Ally McCoist's side eventually made their pressure tell in the 31st minute when Stenhousemuir failed to clear the danger from a throw-in. The defensive indecision allowed Daly to head into the path of Smith and the left-back fired a powerful shot past Chris Smith from 20 yards.
Rangers doubled their advantage just five minutes later. Law's acute pass sent Shiels through on goal and the midfielder used the outside of his boot to cleverly beat Smith with a composed finish.
Kyle Hutton missed the target from long-range and Daly shot straight at Smith as the champions made a strong start to the second half.
Stenhousemuir came close to getting a goal back when Joshua Watt linked up with Ciaran Summers down the left and his cut-back found Dickson, whose shot took a deflection and drifted narrowly wide of the post.
The game was over as a contest on 65 minutes. A high ball was flicked on by Daly into the path of Law, who burst into the box and was brought down by Duncan as he prepared to shoot, resulting in a penalty and a red card. McCulloch stepped up and converted into the bottom-left corner for his 17th league goal of the season.
Greenhalgh was just off-target with a free-kick for Scott Booth's men, but Rangers continued to control proceedings and the fourth goal arrived on 78 minutes. Substitute Nicky Clark found Law in space outside the penalty area and the midfielder blasted a terrific shot past Smith.
It should have been five before the close when Clark was played in vy debutant Charlie Telfer but was somehow denied by a combination of Smith and two defenders with the goal at his mercy.