The Ivorian exchanged passes with David Silva and Carlos Tevez before slotting home and Aguero doubled the lead on 14 minutes from the penalty spot.
Tevez bundled in a third after 52 and Aguero rifled in the fourth 16 minutes from time.
FA Cup draw
FA Cup holders Chelsea could face Premier League leaders Manchester United at Old Trafford in the quarter-finals if both win fifth-round ties.
United would need to beat Reading in their last-16 meeting yesterday while Chelsea, who crushed Brentford 4-0 in a fourth-round replay on Sunday, have to get past Championship (second division) Middlesbrough, who they meet at the Riverside on Feb. 27.
United last reached the FA Cup final in 2007 which they lost 1-0 to Chelsea at Wembley, with Didier Drogba scoring the winner late in extra time.
Manchester City, winners in 2011, were drawn at home to Championship side Barnsley.
Sunday’s last-eight draw created another potential all top-flight encounter with Everton hosting Wigan Athletic if David Moyes’ side can get past third-tier Oldham Athletic in a replay at Goodison Park. Oldham scored a stoppage-time equalizer to hold Everton to a 2-2 draw on Saturday.
Blackburn Rovers were rewarded for a shock 1-0 fifth-round win at Arsenal with another trip to the capital, this time to face fellow Championship outfit Millwall, the 2004 finalists.
The matches are to be played on the weekend of March 9 and March 10.