Spurs produced their best performance of the season thus far as they inflicted upon Maurizio Sarri his first loss as Blues manager.
Alli opened the scoring with a first-half header, before Harry Kane and Son Heung-Min netted either side of the break.
Substitute Olivier Giroud scored a late consolation but victory saw the north Londoners jump into third in the table, and stay five points behind leaders Manchester City.
And the England international has demanded his side ensure their standards do not slip as a key run of matches loom.
“We have to keep that as our level,” Alli added. “We can’t drop off, and we have to improve as well.
“We’ve got a busy month and some really tough fixtures, and it gives us confidence going into those games that we can beat anyone.
“Chelsea are a top side, they have some amazing players and they’ve been in great form as well.
“So to perform the way we did, to dominate the game so much, to have so many chances, we’ve got to keep that up.
“Like I said, we just need to keep this form up and improve, not drop off or take our foot off the pedal just because we got a good win.
“We just have to go into the next games, we know how important they are, just focus on the next game, take the positives from this game, and there are still things we need to improve on.”
Tottenham's final game of November sees them host Inter Milan in a must-win game in the Champions League before travelling to The Emirates Stadium to face Arsenal in the first north London derby of the season.
Squad rotation will be critical during one of the most intense periods of the season.
Manager Mauricio Pochettino made five changes for the visit of Chelsea but their performance was unaffected and Alli says the coach is a master of shuffling his pack.
“I think working with Poch you know how good he is,” he added. “He’s an amazing manager tactically.
“A lot of it was the work we did tactically: on the front foot, pushing up high.
“He’s managing the squad well, rotating when he needs to, picking the players that he feels are best on that day.
"That’s important for the team, to have players that are fresh and ready to go. Everyone knows their roles and responsibilities.
“He makes it very clear what you have to do.
“So going into the game, you know your role and what you have to do. You don’t have to worry about anything else, your football is natural, it’s what you’ve been doing for a long time.
“So as long as we’re clear on our roles and responsibilities, we can enjoy playing.”