The Ghanaian effortlessly curled home a cheeky free-kick to put Rafael Benitez's side in the lead on 55 minutes, before Isaac Hayden added the second 10 minutes later.
Newcastle had already secured Premier League promotion before the Championship fixture, but still in with a chance of beating leaders Brighton and Hove Albion to the title, the Magpies are not taking their foot off the pedal.
"I always want to take free-kicks. I'm always confident," Atsu told Sky Sports News after the game.
"We wanted to win because we wanted to put pressure on Brighton.
"We'll watch their game tomorrow and we are expecting something good for us.
"The manager Rafael Benitez gives me a lot of confidence. He comes to the line during the match and tries to encourage me."
Atsu's splendid performance on the night earned him the official Man of the Match award.
With one more game to go, the Ghanaian is close to completing his season-long deal at St. James' Park.
It is unclear whether the Black Star will be joining the Magpies on a permanent contract, but reports say parent club Chelsea have placed a £6.5 million price-tag on the attacker.
The 25-year-old has made 31 Championship appearances involving 14 starts so far.
Friday's strike was his fifth goal for the club, having also assisted three other goals.