Caretaker boss Keith Millen had seen his side snatch an early lead at the City Ground, but this was always going to be Forest's night as they rediscovered the kind of form that rekindled memories of their halcyon days of European Cup success and League titles under Clough.
A Jack Lester penalty and a close-range finish from James Perch had them ahead before the half-hour mark and, by the time Kris Commons added a spectacular third ten minutes after the break, there was only going to be one winner.
Commons had come close to opening the scoring, with a low shot from the edge of the box that Steve Phillips did well to save.
But it was the visitors who shocked Forest by taking the lead, as 20-year-old Steven Gillespie netted his first goal for City, latching on to the end of a pass from veteran strike partner Marcus Stewart and firing a confident finish into the bottom corner on 15 minutes.
In previous weeks Forest would have crumbled in such circumstances, but they never seemed fazed by the set-back and were quickly back in control.
Within a minute they could have had a penalty after Dave Partridge brought down Lester in the box, but referee Scott Mathieson was not convinced.
That was not the case, however, when Jamie Smith and Scott Murray both slid in on Commons after 25 minutes, with Mathieson quickly pointing to the spot and, for the second time in as many games, Lester converted confidently.
Within two minutes, Forest were ahead, with Lester again the integral figure as he exchanged a neat one-two with Commons on the edge of the box, before angling towards goal and firing a vicious cross-cum-shot that Phillips could only parry to Perch at the far post, where the youngster duly rifled home.
By half-time the game should have been all but beyond City, who suddenly found themselves needing to defend desperately.
Scott Brown had to clear off the line as David Johnson struck a crisp 18-yard shot that was arrowing into the bottom corner, before Phillips denied the striker again, this time as he outfought Partridge for possession of a huge clearance on the edge of the box and struck a powerful driven effort that the keeper did well to block with his feet.
After the break, the outcome of the match was quickly decided as, with a breathtaking 25-yard shot into the bottom corner, Commons put Forest 3-1 up and took any remaining wind out of City's sails.
Forest took their foot off the gas, with City posing little threat, although Lester could have extended their lead further and taken his tally to three in two matches, following his return from nine months on the sidelines with a cruciate knee injury, if not for another save from Phillips.
Megson's side had started the weekend in the bottom four of League One, but, following Saturday's win over Rotherham and this success, they find themselves only two points off a play-off place.