Burnley suffered an early blow when in-form striker Steven Thompson was stretchered off after only six minutes to be replaced by teenage starlet Jay Rodriguez.
The Clarets went in front on 19 minutes when a Robbie Blake free-kick from wide on the left evaded both attackers and defenders alike before nestling into the net.
Burnley increased their lead seven minutes before half-time as Blake teased and tormented the Forest defence before picking out Wade Elliott to score.
Two goals in four minutes made the game safe as a Graham Alexander free-kick found striker Martin Paterson, who crossed for central defender Clarke Carlisle to score with a header.
Teenager Rodriguez made it 4-0 on 55 minutes when he collected a short pass from Blake and curled an outstanding right-foot shot beyond Forest goalkeeper Paul Smith.
Burnley substitute Joey Gudjonsson went close to extending the lead even further when he hammered a 30-yard free-kick just wide of the target.
But the home side did not have to wait long for their fifth goal as the Forest defence could only clear a cross from Chris Eagles as far as Gudjonsson, who volleyed the ball past a helpless Smith.
While the victory will encourage Owen Coyle's team in their bid to make the play-offs, the result will do little for the confidence of Forest, who will be living on their nerves with many more performances like this.