Tammy Abraham and Christian Pulisic got on the scoresheet for Frank Lampard’s men while Gerard Deulofeu halved the deficit by putting away a VAR awarded spot kick.
Chelsea move above Leicester City, who are away at Crystal Palace on Sunday, into third place while Watford remain bottom of the pile.
With only five minutes on the clock, Chelsea took the lead and it came courtesy Tammy Abraham’s ninth league goal of the season.
Jorginho hit a delightful one-time pass beyond the Watford defence, allowing the ever-alert Abraham to lift the ball over the advancing Ben Foster.
Chelsea were denied a second by Foster in the 20th minute as the goalkeeper denied Abraham from close range following a deflected Mason Mount effort and minutes later the 36-year-old former England international produced an even better stop when he kept out Christian Pulisic’s header from a corner.
Out of nothing, Watford produced their best effort through Gerard Deulofeu, but the Spaniard’s low shot from outside the box flashed just wide.
Mount forced Foster into action with a dipping long range effort which was tipped onto the crossbar in the 43rd minute.
Five minutes after the break, Willian fed an unmarked Mount in the Watford penalty area but once again Foster maintained the hosts’ interest in the game with a good save.
Abraham turned provider when his cut back picked out Pulisic, who tapped home his fourth Premier League goal in a week in the 54th minute.
Four minutes later, the USA international was denied by Foster’s left boot as Chelsea threatened to inflict further damage.
Chelsea were guilty of over-playing at the back and the visitors gave away a silly penalty when Jorginho clipped Deulofeu in the box, allowing the former Barcelona man to tuck home a VAR-awarded penalty with eleven minutes to play.
Watford came close to equalizing in the closing seconds as they threw all men forward and it was goalkeeper Foster’s header that nearly nicked a point for the hosts but Kepa Arrizabalaga pulled off a brilliant save to deny his opposite number.
