Their impressive Premier League form has seem them close the gap on leaders Chelsea to just four points after a run of six wins in a row. The blues, however, could increase the gap back to seven points later today as they play Bournemouth in the late kick-off.
Eric Dier and Son Heung-min quickly added two goals to pile the misery on Watford, putting them 3-0 behind at half-time.
Son added to his first with a fine finish early in the second half to lead his side to a terrific 4-0 victory.
Spurs Spectacular in First Half
Hot off an unbelievable comeback in midweek, Spurs put on a show for their home fans as they looked to maintain pressure on league leaders Chelsea. Despite Watford starting well, it was Mauricio Pochettino's men who came closest to opening the scoring. Son struck the post early on, and only a minute later Watford goalkeeper Hueurelho Gomes was called into action on his return to North London to deny Vincent Janssen from scoring his first Premier League goal from open play.
Spurs started to control the game, putting Watford on the back foot for much of the first half. Frustrations started to build as Janssen missed a sitter. The Dutch international watched the ball hit off his thigh onto the crossbar from just a few yards out.
From an easy miss to an excellent strike - Alli gave Spurs the lead on the 33rd minute with a curling effort from 25 yards out. Watford were left helpless and could do nothing but watch as it curled magnificently into the far bottom corner.
5 minutes later, Spurs were 2-0 up. Son's deflected cross fell perfectly into the path of Dier on the edge of the penalty area for him to strike powerfully past a helpless Gomes.
A minute before the interval it was 3-0, with yet another delightful Spurs goal. An unmarked Son picked up the ball from 30 yards out and struck a low, powerful strike into the bottom corner. Watford's defence were struggling to deal with the quality of Spurs' offensive threats.
Kane returns from injury spell
Watford continued to struggle against the fluidity of Spurs' attacking football. Just nine minutes into the second half, Son killed the game with his second and Spurs' fourth. He met teammate Kieran Trippier's deep cross with a delightful finish past Gomes making it 4-0.
Harry Kane almost returned to the side with a goal, as he failed to get on the end of another brilliant Trippier cross and then struck the bar late in the game with a free-kick.
Son will be kicking himself after failing to get his hat-trick. After missing a simple chance and striking the woodwork, the South Korean just could not find his third to claim the match ball.
Where does this leave both sides?
Spurs remain in second-place behind leaders Chelsea, however the gap has now been cut to four points. The gap could be increased back to seven points if Chelsea defeat Bournemouth later today.
Watford stay in 10th place, nonetheless if Stoke are to get a result at home to Liverpool then Walter Mazzarri's side will drop into the bottom half of the table to 11th.