Bale briefly gave Tottenham hope of a fightback with a goal on 56 minutes to make it 2-1 but a sublime finish from Ramires, a stunning 35-yard free-kick from Lampard and a late effort from Malouda took Chelsea out of sight.
Chelsea captain John Terry later admitted Mata's hugely controversial goal should not have been awarded.
"I thought Mata's strike hit me and didn't go over (the line), but the linesman's seen it and given it," Terry told BBC radio.
"I honestly don't think it went over the line but the linesman gave it and there's nothing we can do about that. Spurs are one of the best sides in the league. It was a great performance and a great result."
Earlier, Tottenham appeared to be the likeliest to break the deadlock in a first half that was slow to get going, only to be denied by the woodwork and a goal-line clearance from Terry.
Terry's last-ditch heroics came on 36 minutes when he blocked a close-range header from Rafael van der Vaart.
Four minutes later Spurs threatened again, when van der Vaart's long ball forward for Emmanuel Adebayor missed everyone and rattled the upright.
Yet just when it seemed Spurs were on the verge of an opener, Chelsea took the lead with a goal on 43 minutes that owed everything to the raw power of Drogba.
A long ball forward from Lampard found the Ivorian, who held off William Gallas and turned before crashing an unstoppable shot past Carlo Cudicini for 1-0.
Chelsea doubled their lead in controversial circumstances from the corner.
Cudicini pulled off another stunning block to keep away David Luiz's near-post header, but the ball fell only as far as Mata.
The No.10's shot flew hard and low into the goal-mouth and hit a tangle of bodies on the goal-line.
Referee Atkinson hesitated before awarding the goal but television replays appeared to show that the ball had not crossed the line.
Tottenham's players protested but Mata and Chelsea celebrated a 2-0 lead.
-AAP
