Chelsea brushed aside Watford to book a fourth round tie with Scarborough.
Adrian Mutu flicked home to give Chelsea an early first-half lead and Jimmy Floyd Hasselbaink added a second with a consummate piece of finishing.
The striking masterclass continued as Mutu bettered Hasselbaink's finish with a curling shot as did Eidur Gudjohnsen with a deftly executed chip.
Watford's Jamie Hand hit the post while Gavin Mahon went close with a shot to almost embarrass Carlo Cudicini.
Initially showing no signs of nerves Watford went on the offensive forcing four corners in the opening five minutes as Ray Lewington's side pinned Chelsea in their own half.
Lee Cook's corner in particular caused panic in the Chelsea penalty box as the ball skimmed through a crowded area, before Hasselbaink cleared the danger.
Despite that promising opening Watford found themselves a goal down after just seven minutes.
Lenny Pidgeley did well to parry Frank Lampard's fierce shot, but the ball rebounded off Neil Ardley into the path of Mutu, who nonchalantly flicked home.
The goal punctured some of Watford's optimism and Pidgeley had to come out quickly three times to smother the ball as Chelsea threatened.
Chelsea's approach play also began to acquire more fluency, though two incisive moves ended with Claude Makelele and Hasselbaink shooting wide.
Just past the half-hour a rare Watford attack ended with Jamie Hand bustling past William Gallas and John Terry and unleash a half-volley that rebounded off the woodwork.
Moments later Hasselbaink all but extinguished Watford's hopes of causing an upset as he killed Gallas' long pass with one touch before rifling the ball past Pidgeley.
Jesper Gronkjaer increasingly began to come in the game and his pace and drive down the right caused Watford repeated problems.
Watford refused to let their heads drop, though their attacks became more and more frequent, with their best effort coming from a Gavin Mahon shot.
Substitute Scott Fitzgerald also almost embarrassed Carlo Cudicini but soon after Mutu deftly brought the ball down and curled his shot past Pidgeley, to claim his third goal in two games.
Eidur Gudjohnsen completed the rout with a sweetly executed chip past the young Watford goalkeeper, who on-loan from Chelsea, was playing at Stamford Bridge for only the second time.
Chelsea: Cudicini, Melchiot, Terry, Gallas (Huth 82), Babayaro,
Gronkjaer, Lampard, Makelele, Cole, Mutu (Duff 80),
Hasselbaink (Gudjohnsen 70).
Subs Not Used: Sullivan, Johnson.
Watford: Pidgeley, Ardley, Cox, Gayle, Smith, Devlin, Hyde,
Mahon, Hand (Doyley 82), Cook (Fitzgerald 58), Dyer (Webber 58).
Subs Not Used: Chamberlain, Brown.
Referee: A Wiley (Staffordshire).