The Brazilian had not scored since the 8-0 rout at Sheffield United in September but opened the scoring at the City Ground and then netted the winner in the second half.
Fabian Schar also scored as the Magpies moved seventh, two points behind sixth-placed Manchester United, and after an inconsistent season they will now be eyeing a run of form which sees them book European football for a second successive season.
Forest twice drew level through Anthony Elanga and Callum Hudson-Odoi and thought they should have had a penalty at 2-2, but they are still searching for a first Premier League win of 2024 and are just two points above the relegation zone.
And with a possible points deduction from the Premier League hanging over their heads, there will be real concerns going into the final third of the season.
Their cause is not helped by continually losing games they are competing in as this was the sixth time they have lost 3-2 this season.
The tone for a breathless match was set in the fifth minute as Forest could have led from an excellent chance for Morgan Gibbs-White.
Five minutes later the hosts were behind as Guimaraes ghosted in at the far post to produce a fine first-time finish from Kieran Trippier’s deep cross.
And the long-legged defender was left in the dust by the Sweden international as Nicolas Dominguez’s through-ball sent him clear, but Newcastle goalkeeper Martin Dubravka stayed big and made a good stop.
Elanga was not so wasteful with his next chance 10 minutes later as he again put on the afterburners to leave Burn and Sven Botman in his wake, coolly slotting through Dubravka’s legs from Gibbs-White’s excellent through-ball.
Forest were pushing for a second but Newcastle regained the lead in the 43rd minute.
Botman headed down Trippier’s free-kick into the path of Schar, who guided the ball cleanly into the bottom corner from 12 yards.
It was 2-2 in the sixth minute of first-half added time as Hudson-Odoi cut inside from the left and let fly with an effort that clipped Lewis Miley and soared into the corner.
Forest continued to have joy against Newcastle’s high line and thought they should have had a penalty just after the hour.
Awoniyi raced through on goal from Matz Sels’ long kick and looked to be tripped by Dubravka’s outstretched arm, but referee Anthony Taylor did not give a penalty and VAR did not overrule despite a check.
Typically, three minutes later Newcastle went ahead for the third time as Elanga’s loose pass went straight to Guimaraes, who found the bottom corner for his second of the night.
This time Newcastle did not relinquish their advantage and saw it out for a valuable three points.