Real Madrid took a huge stride towards the Champions League semi-finals by brushing aside Galatasaray in the first leg of their quarter-final tie.
Cristiano Ronaldo handed the hosts an early lead by chipping over goalkeeper Fernando Muslera.
Karim Benzema deftly controlled Essien's cross to stroke in the second, before substitute Gonzalo Higuain nodded in after the break.
Didier Drogba and Emmanuel Eboue wasted the Turkish champions' best chances.
Galatasaray were far from outclassed in the opening 70 minutes and created a number of decent opportunities, particularly in the first half, as they searched for a vital away goal.
But a lethal combination of Real's array of attacking talent and three defensive lapses had already proved the difference before Fatih Terim's team ran out of steam in the closing stages.
Argentine striker Higuain, who replaced fellow goalscorer Benzema eight minutes earlier, put the gloss on a comfortable home display at the Bernabeu and left Galatasaray facing a difficult task in the return leg in Istanbul on 9 April.
Real Madrid's boss Jose Mourinho stressed the importance of Champions League success to the Spaniards after conceding the Primera Division title was beyond his side - they trail leaders Barcelona by 13 points.
And his team, aiming for a record 24th semi-final appearance in Europe's premier club competition, made the perfect start against Galatasaray.
Ronaldo latched on to Ozil's perfectly-weighted through ball and almost nonchalantly lifted the ball over a helpless Muslera after only nine minutes.
However, Galatasaray seemed unfazed by the early setback and responded well, neatly maintaining possession.
Much of the pre-match build-up had centred on the meeting between Drogba and his former Chelsea mentor Mourinho, and the Portuguese boss must have been concerned when the Ivorian forward forged a clear sight of goal shortly after Ronaldo's opener.
Galatasaray striker Drogba brushed aside home defender Raphael Varane to turn on the edge of the Real penalty area but could only fire wildly over the crossbar.
Moments later the powerful forward, who netted Chelsea's winning penalty in last season's Champions League final, unleashed a 20-yard shot which Real goalkeeper Diego Lopez unconvincingly punched clear.
But Galatasaray were left to rue those missed opportunities as Benzema doubled Madrid's advantage.
Essien swung in a deep cross from the right flank and Eboue inexplicably ducked away from it, allowing Benzema to kill the ball before placing a firm shot inside the near post.
Former Arsenal defender Eboue could have made amends within seconds, only to fire straight at Lopez's legs after playing a neat one-two with Drogba.
Galatasaray boss Terim sacrificed attacking midfielder Wesley Sneijder for central defender Gokhan Zan at the interval in a bid to provide a more solid platform for his team.
The switch enabled them to stifle Real's attacking intent, but also deprived them of an effective link between their midfield three and strikers Drogba and Burak Yilmaz.
Clear-cut chances had been rare after the interval before Ozil side-footed at Muslera after he was picked out in the Galatasaray penalty area by Xabi Alonso's sublime lofted pass.
And it was Spain midfielder Alonso who provided another perfect delivery, this time from a deep free-kick, to enable an unmarked Higuain to net his first Champions League goal of the season and give Real what looks like being a decisive advantage to take to Turkey for the return leg.