Midfield star Alli scored on the field, his 19th goal of the season, during the 4-0 thrashing of the Hornets before parting with beauty Melissa Howe.
The England talent turns 21 on Tuesday but invited pals to a bash at west Londond hot spot Club No.41.
Guest and Twitter user Eiron tweeted: “The amount of bottles of don perignon, magnum belvedere and moet that was there was actually a joke.
“Alli was so frassed by the end of it.”
Howe is famed for her association with footballers having previously been seen out with former Arsenal striker Marouane Chamakh and Ashley Cole.
Alli, who is dating model Ruby Mae, slurred “I am not your slave” to 200 mates as they sang Happy Birthday to him.
He was given a specially made birthday cake with the graphic “Dele 21” and candles on it.
Another guest told The Sun : “It was a raucous night. Dele was having a brilliant time and spoke to everyone.
“He was the centre of attention as you might expect – especially with the women.
“It was noticeable just how many sexy young women were invited to the party.”
Former MK Dons wonderkid Alli has played his part in 40 top flight goals to make him more lethal than Frank Lampard, Steven Gerrard and David Beckham put together.
Alli moved to White Hart Lane in 2015 on a five year deal – with Spurs spending an initial £5m.