The Hammers had previously only found the net four times in the top flight this term, but three goals in the space of 13 minutes earned them a memorable win against a shell-shocked Spurs.
Winston Reid bundled in the opener from close range after his initial header was blocked, and Ricardo Vaz Te added a second on 72 minutes when Hugo Lloris parried his shot against him and back into the goal.
Ravel Morrison capped off a wonderful afternoon for Sam Allardyce's side in the 80th minute with a solo effort, which started with him on the halfway line and finished with him securing the Iron's first Premier League win at Tottenham since 1999.
Below, Sports Mole analyses whether the result was reflective of the action in North London.
On target: 5
On target: 5
Was the result fair? In the end, it was, but the scoreline does slightly flatter West Ham. The opening goal was always going to be key in this match, and when Spurs failed to get it during their periods of dominance in the first half and start of the second, they were in trouble. The visitors threatened from set pieces all afternoon and Reid's close-range strike was the key moment in the game. Vaz Te and Morrison scored on the break to add some gloss to a fantastic result, and although there was an element of luck to a couple of the Hammers goals, Allardyce will argue that they were due some good fortune.
Tottenham's performance: Not good. Christian Eriksen was marked out of the game as West Ham packed the middle of the park. Andros Townsend was outstanding for the first hour but only Paulinho really committed himself to advancing into the box on a regular basis to get on the end of any of his crosses. There was no width on the left, with Danny Rose absent and both Kyle Naughton and Gylfi Sigurdsson inclined to cut inside. At the other end, they have been shaky from set pieces all season and Reid's goal was the second that they have conceded from them in as many games.
West Ham's performance: Allardyce set his team up perfectly to play at Spurs, putting plenty of men behind the ball, restricting their creative players of room in the middle of the park and forcing the hosts to use the wings. When Spurs were establishing a period of pressure, James Tomkins and Reid were excellent in central defence, and both were always a danger from corners, from which Stewart Downing's delivery was consistently good. They didn't have that much of the ball, but, especially after taking the lead, they looked likely to do something with it and they put the game to bed with two goals on the break.
Sports Mole's man of the match
Winston Reid: The New Zealand defender was a rock alongside Tomkins at centre-back and rarely allowed Jermain Defoe space to run in behind or get a shot away. Mark Noble and Mohamed Diame were also excellent in central midfield, but Reid's goal was a game-changer. He was a real threat from set pieces and eventually punished Tottenham with his aerial prowess.
Tottenham will be thinking that they could have defended better for all three of West Ham's goals, but Walker's poor positioning for the second allowed Vaz Ze a free run through the middle and the Portuguese forward capitalised by netting the goal that killed the game off.
Referee's performance: Lee Probert had a quiet afternoon, which he may not have been expecting, given that he was officiating a London derby. He did not brandish a single yellow card throughout the contest and allowed the play to flow, despite their being several forceful tackles.
Spurs: Tottenham will have the international break to figure out what went wrong this afternoon and address those problems when they travel to Aston Villa in a fortnight.
West Ham: A difficult match against Manchester City at Upton Park, but they will certainly will be full of confidence on the back of this result for the visit of the Blues.