United's youngsters found the net on four occasions in the opening 20 minutes of their quarter-final clash, with Watts scoring the Magpies' fourth with a terrific left-footed effort which flew into the far corner from the edge of the penalty area.
Ben Dawson's side led 5-2 before the half-time whistle, with Yannick Touré scoring a brace along with strikes from Juanito and Rosaire Longelo.
Watts added both of Newcastle's second-half goals, including a close-range header before the 19-year-old sealing his treble with a right-footed strike in the dying stages.
However, the Alnwick-born player admitted it wasn't the first time he had netted a perfect hat-trick during his surge through the youth levels of United's Academy.
"The last time I scored a perfect hat-trick was against Everton playing for the under-16s," Watts told nufc.co.uk. "I also scored three in an FA Youth Cup match (against Brighton) last season but it wasn't a perfect hat-trick!
"To score a treble in one game wasn't something I was expecting this season as I've been playing at the back but with all the goals we scored against Blyth, it wasn't as if I wanted to be the one to score. We know it is a team game at the end of the day and the build-up play and passing is just as important as finishing off the chances we created."
Watts, who has played at the heart of Newcastle's defence this term, featured in central midfield alongside Matthew Longstaff and demonstrated his capability of playing in either position, with United's youngsters bidding to win the competition for a 38th time.
"I'm a versatile player and like to play anywhere the manager says," Watts added. "I don't have a preferred position and I just try to give 100 per cent wherever I play. I have been playing as a centre-half for the majority of the season and when I got told I'd be playing in midfield, I thought I'd use my elements of playing as a centre-back in a positive way in order to help the team out as much as possible.
"It's a good cup to be a part of. It's a good opportunity because we're in this competition to win it. As a squad, we feel we are good enough that we can go all the way and achieving silverware would be brilliant."
Watts, an England under-19 international, was shocked by the manner of the scoreline after a frantic first-half and, despite the heavy scoreline, expressed United's desire in attempting to shut out their opponents.
"It was a bit of a seven-goal thriller in the first 45 minutes and something I haven't experienced before," he said. "Going in at the break winning 5-2, our main focus was trying not to concede in the second half and it was pleasing that we managed to do that as it showed we were a bit more professional in the way we were going about things in the second half.
"One of the things we wanted to do before the game was to keep a clean sheet. It has been something the team are looking to crack down on but, despite the disappointment of conceding two goals there were still lots of positives to take going into the game against Southampton (on Friday night)."
