There was no hint of the second-half goal avalanche to come when Celtic led by just one John Hartson goal at the interval.
But once Aiden McGeady had scored the second goal, Celtic added a further three goals in a six-minute spell through Hartson and a Stilian Petrov double before substitute Craig Beattie headed home their sixth goal with a minute to go.
The difference in class between the teams was there for all to see and there was little for Dunfermline to take from this match.
Celtic made a bright start and Stanislav Varga went down in the box under a challenge from Andy Tod, but his penalty claim was waved away. Hartson then slipped a ball through to Petrov but Scott Wilson's tackle denied the Bulgarian a shooting opportunity.
Celtic took the lead after Craig Bellamy had been fouled out on the right wing. Alan Thompson took the resultant free-kick and his inswinging cross was guided home by Hartson with a clever finish.
Bellamy blazed a shot well over from McGeady's cut-back as the Republic of Ireland winger proceeded to give Greg Ross a torrid afternoon.
Dunfermline's solitary attack of the afternoon ended with Barry Nicholson's first effort being blocked and his shot from the rebound was held by Robert Douglas in the Celtic goal.
Bellamy then turned Ross brilliantly but Thompson's shot lacked power. Derek Stillie in the Dunfermline goal then produced a marvellous save to deny Hartson's shot on the turn from another astute Bellamy cross.
Hartson then burst along the byline but his pass just failed to reach Jackie McNamara who was standing unmarked in front of goal.
Thompson released Ulrik Laursen with a marvellous pass inside Ross, but the ball bobbled as the Dane went to cross and the chance was lost.
Bellamy just failed to reach Neil Lennon's pass as Celtic sought a crucial second goal before the interval.
At the start of the second half McGeady showed defensive awareness, to add to his marvellous talents going forward, as he tracked back to cover Ross before dispossessing the wing-back. The Celtic youngster then saw his well-struck shot deflect off Hartson before he finally scored.
Picking up Bellamy's pass, McGeady cut inside Ross before unleashing a 20-yard right-foot drive which beat Stillie at his near post.
Celtic seemed to relax at this stage and hit Dunfermline with a three-goal blitz in a six-minute spell. Bellamy's cross was deflected behind, but when McGeady's quick corner found him he quickly transferred the ball to his fellow Welshman Hartson who nudged the ball home from close range.
Stillie did well to smother McNamara's shot at his post before Celtic got a fourth. Again Bellamy was involved and from his cross on the left Petrov volleyed home from six yards.
The visitors were completely shell-shocked by this stage and McGeady threaded a superb pass through to Petrov whose first effort was blocked on the line by Scott Wilson before he lashed the ball high into the net.
At this stage Dunfermline must have feared what the scoreline was going to be at the final whistle and they were relieved to concede only one more goal before the end.
Hartson's effort was just wide from McNamara's cross and Stillie performed heroics to hold Bellamy's shot after a slick one-two with Hartson.
Bobo Balde's powerful header from Thompson's cross was touched over by the Dunfermline keeper before Celtic's two late substitutes combined to score the sixth.
Ross Wallace, who had replaced the outstanding McGeady, tormented Ross further before crossing for Beattie to glance his header home at the near post and finally bringing Dunfermline's suffering to an end.
MAN OF THE MATCH: Aiden McGeady (Celtic) - The Republic of Ireland youngster gave Greg Ross an afternoon to forget. But as well as scoring the vital second goal and adding much to Celtic's attacking options, McGeady showed his versatility by making several timely tackles in defence.