The Spurs striker headed home substitute Ivan Perisic’s corner in the sixth minute of added time.
The Blues took the lead twice, first through Kalidou Koulibaly, volleying a superb volley to score his first goal for the club, and Rhys James.
Pierre-Emile Hojbjerg scored Spurs’ other goal either side of Chelsea strikes.
Both teams have four points from two games, with Spurs in fourth and Chelsea in seventh.
Forest enjoy the return of your dreams
Nottingham Forest’s first home Premier League game in 23 years ended on a high as Taiwo Awoniyi’s first-half strike proved decisive in a 1-0 win against West Ham United.
The striker went close in first-half stoppage time after the ball was deflected into his path.
However, visitors will wonder how they left the City Ground empty-handed.
Pablo Fornals and Said Benrahma both hit the woodwork, while the biggest chance fell to Declan Rice, whose 65th-minute penalty, awarded for a handball by Scott McKenna after a VAR review, was saved by Dean Henderson.
A first win of the season lifts Forest to 10th with three points, while back-to-back defeats leave West Ham in 19th.
More drama on Monday?
An exciting Matchweek isn’t over yet, with Liverpool and Crystal Palace both looking to secure their first win of the season when they meet at Anfield on Monday.
Darwin Nunez will be hoping to earn a first Premier League start for the Reds after coming off the bench to score a goal and assist in last weekend’s 2-2 draw at Fulham.
