The midfielder bent spectacular 20-yard shots inside the post in the 10th and 37th minutes to steer Colin Calderwood's side to their second victory over Brentford in the space of a week.
And they were further boosted by a late substitute appearance from Nathan Tyson, who had been sidelined since the opening day of the season with a medial knee ligament injury.
But it was Commons who grabbed the headlines. He made a lively start and, within ten minutes, had put the home side ahead in trademark fashion.
When Neil Harris was brought down on the edge of the box in a central position, Commons curled a deft low shot around the wall and into the bottom corner of the net.
Brentford's only real threat had come in the form of a speculative effort from Charlie Ide, who turned well on the edge of the box but rifled a shot narrowly over.
Forest won a succession of corners, as they increased the pressure on the Brentford goal, with skipper Ian Breckin planting one header into the sidenetting and looping another over the bar, from pinpoint deliveries from Nicky Southall.
And the visitors were punished in emphatic fashion as they conceded another free-kick on the edge of the box, this time for a foul on Agogo.
From almost an identical position, Commons struck again in carbon copy fashion, bending another crisply struck drive around the wall and beyond the despairing dive of Clark Masters.
Brentford introduced veteran striker Clyde Wijnhard at the interval and the move did provide them with a little more attacking threat.
But when John Mousinho broke menacingly, clear of the defence wide on the right, he failed to make the most of the opportunity with a poor cross that was easily cleared by Sammy Clingan.
Forest were lifted by an unexpected appearance from Tyson, their talismanic striker, who managed 25 minutes as a substitute, during which time he almost scored with a brave diving header, which Masters saved well.