The striker scored his first Premier League goal since a September brace against the same opposition as the visitors came from behind to win 3-1.
Lukaku has now scored nine goals in his last 10 top-flight appearances against Villa and also caused havoc to win a stoppage-time penalty for Jorginho to score his second goal of the game.
His first season back in England has been hampered by an ankle injury but the Belgium international now has two in his last three games to offer Thomas Tuchel a welcome boost after Chelsea dropped off the title race pace.
They now sit six points behind Manchester City and level on points with second-placed Liverpool.
Jorginho’s first penalty had earlier cancelled out Reece James’ own goal as Villa ran out of steam after an impressive opening half to remain 10th.
Without their boss Steven Gerrard, absent after contracting Covid, the hosts initially went about their business efficiently and with purpose on Boxing Day.
Bullish Villa looked to unsettle Chelsea and Thiago Silva deflected Danny Ings’ drive wide after Matty Cash seized on Marcos Alonso’s poor touch.
Without midfield enforcer John McGinn, so often the driving force, there was still an energy and ingenuity from the hosts and only Trevoh Chalobah’s fine recovery block denied Ollie Watkins after 19 minutes.
Mason Mount’s curling effort bounced off the top of the bar yet Villa broke the deadlock after 28 minutes.
There was a huge slice of fortune, though one Villa deserved, when James rose to meet Matt Targett’s left-wing cross but only succeeded in diverting it over Edouard Mendy and into the far corner.
On the balance of play it was a fair lead but Villa gifted Chelsea a way back six minutes later when Cash recklessly dived in on Callum Hudson-Odoi in the area and Jorginho stepped up to convert from the spot.
Villa remained undeterred and continued to stretch the visitors, with Mendy needing to rush out to clear at the feet of Watkins.
Another Chalobah block kept Ings out and Tuchel would have been wary of the space Villa were creating.
Three wins in their previous eight games in all competitions have seen Chelsea stumble consistently for the first time under Tuchel.
There is no real jeopardy or threat to their place in the top four – they are 11 points clear of Tottenham in fifth – but Tuchel was concerned enough to replace Chalobah with Lukaku at the break.
His presence rattled Villa immediately, forcing Emi Martinez to punch clear and going close to reaching Mount’s cross.
It changed Chelsea’s gameplan and there was little surprise when he ended his Premier League drought after 56 minutes. Hudson-Odoi’s excellent cross found the striker drifting in ahead of a dozing Tyrone Mings and he expertly glanced in from seven yards.
Mount should have added a third soon after when he beat Martinez to the ball but, with four defenders between him and the goal, dragged wide.
Villa had struggled to maintain their first-half momentum and managed to up the tempo with 15 minutes remaining, but with little progress as Anwar El Ghazi’s strike failed to trouble Mendy.
But fittingly, after a smart Martinez stop denied Hudson-Odoi, it was Lukaku who made the telling impact once more in stoppage time. Ezri Konsa brought him down and Jorginho wrapped up the points from the spot.