The win at Bloomfield Road on Tuesday night was the Young Lions' sixth out of their six games this calendar year, a sequence in which they have not conceded a single goal.
For what was their first fixture since the controversial Euro 2013 play-off victory in Serbia last month, Pearce took the opportunity to experiment ahead of next summer's finals in Israel, making eight changes to his starting line-up.
That included bringing two debutants in to the first XI, while a further five made their bows from the bench, and following Connor Wickham's 45th-minute header, one of those substitutes, Benik Afobe, won and converted a penalty in the 77th minute to wrap up a comfortable triumph.
Reflecting on his team's efforts, Pearce said: "I think across the board - keeping another clean sheet, winning another game, winning every game this year - the players must take a lot of credit.
"In all honesty, it (the performance in the Northern Ireland game) was beyond my expectations, having brought a group of players together (for it) with five or six who were fresh to the squad.
"I was very pleased with the way we played. The idea with this game was to help develop a pool of players who will be in competition with each other when I come to pick a squad for the summer.
"I think it served exactly the purpose we needed it to."
Pearce has been delighted to see Wickham enjoying himself with England Under-21s during a frustrating period with his club Sunderland.
The striker has been in fine form for the Young Lions, with his goal against Northern Ireland taking his tally to three in his last four appearances for the team.
At club level, though, he has barely had a chance to showcase his ability this term, only making his first Black Cats appearance of the campaign as an 89th-minute substitute in last weekend's 2-1 Barclays Premier League defeat at Everton.
Wickham - who had a considerable reputation when he joined Sunderland for around £8million from Ipswich in 2011 - has made just five top-flight starts in total for the north-east outfit, has only scored once for them and is reportedly set to go out on loan to an npower Championship side.
Pearce has been happy to give the 19-year-old an opportunity, something he feels the player is relishing.
"He is not playing regularly and we need to make sure we supplement his confidence and fitness, and that we get to see his ability on occasions at under-21 level," Pearce said.
"I think he showed that (against Northern Ireland) and he looks as though he is enjoying himself out there.
"I see his demeanour around the place and he is enjoying meeting up with us."