Courtney Vacher's team entered the clash at the Armco Arena on a high, having reached the final of the Bluefin Sports Insurance Women's Cup last weekend, and imposed themselves on Pompey from the off.
A first-half effort from Jasmine McQuade put the young Magpies firmly in the driving seat heading into the break, before Sharna Wilkinson doubled the lead shortly after the restart. Georgina Spraggon put the icing on the cake deep into injury-time with a well-taken finish, putting the result beyond any doubt.
Newcastle dominated the final from the first whistle, and lifting the trophy following the triumph was no more than Vacher's side deserved for putting in a professional performance way beyond their years.
Speaking to nufc.co.uk immediately after the match concluded, the development team's manager said: "Winning on any occasion is a tremendous achievement but to win in the way that the girls did today, I couldn't be prouder of them.
"It was an absolutely dominant display from the off and that continued all the way through to the final whistle, so to come away with the trophy today meant a lot to me, meant a lot to the girls, and hopefully it will mean a lot to the club as well."
McQuade, who was named the FAWNL Player of the Match, echoed Vacher's joy. "It's the first final I've been in as well, and for the girls to come through (and win is brilliant)," she said.
"A lot of them are quite young and for us to win the whole tournament and every game, with none of them going to extra-time, we're just buzzing about it, and obviously to be handed Player of the Match is nice as well."
Newcastle United Women development team: Frankie Hackett, Erin Nelson (Molly Wilcock 66), Sharna Wilkinson (Ava Chapman 76), Jess Spark (Georgie Leech 31), Jasmine McQuade (c), Amy Hargrave, Ebonie Knox (Georgina Spraggon 50), Mel Brooks, Libby Corney, Lily West (Sophie Curle 57), Emily Bloomer
Subs not used: None
Photograph courtesy of Colin Lock/@Tyneside_NUWFC