"It is definitely the best game I've ever been involved in," Lascelles recalls when asked about the Magpies' unforgettable 4-1 Champions League triumph over Paris Saint-Germain. "Playing against that level of opposition at home in the Champions League and to then beat them 4-1 - it was an unreal night.
"I was adamant we'd beat them. There's not a team on the planet that can come to St. James' and have their own way regardless of individuals, the badge they play for or how much money they've been bought for."
The Magpies head into this afternoon's Premier League encounter against Crystal Palace vying for a fifth competitive victory in a row at St. James' Park, with Lascelles starting United's last four competitive matches.
The home crowd, on countless occasions, have proved a key component towards the club's seven-game unbeaten streak, with Lascelles fully aware of the supporters' matchday role, expertly highlighted in their previous home fixture against the French heavyweights.
"Coming here, nobody is going to match our intensity, our passion and hunger as well as the fans' desire and how loud they are", he says. "As a human being, it doesn't matter how good you are - it's intimidating.
"We'll always have the fans on our side, that's a given, and then it's down to us as players to start the games fast, on the front foot and be aggressive. If we can beat them at that, the rest will take care of itself.
"That's exactly what the manager wanted from us and I think we implemented it perfectly (against PSG)."
It was only seven years ago that Lascelles featured against Rotherham United in a narrow 1-0 win at the New York Stadium, elevating the Magpies within three points off the summit of the Championship.
Approaching a decade since joining United as an eager 20-year-old, it has been a commendable journey for the loyal centre-back, who helped contain a star-studded frontline involving three players who featured in last year's World Cup final, including prolific frontman Kylian Mbappé, in football's elite club competition.
"You dream of being a footballer and making it but to captain the side and beat PSG 4-1 is something, if I'm being honest, I never thought I'd really be involved in.
"When we were lining up and hearing the Champions League anthem, I managed to take that in and then the noise at full-time was crazy. It's exciting times at Newcastle for everyone involved.
"I'd been used to something a lot different which was staying in the league and fighting for survival every year. To be in this situation now is really special. It's something new to me but one I'm really enjoying. I'm enjoying every minute of it.
"I've had some amazing days here, gaining promotion and playing in the Premier League since I've been captain and we've also had some dark days but I think that was a special moment for me and my family in captaining this team on such an iconic night.
"A lot of fans still talk about the Barcelona win (in 1997) where Tino Asprilla scored the hat-trick but I think the game against PSG might have been slightly better."
It was also a fitting ending to Lascelles' European bow in witnessing Fabian Schär nestle a stunning 25-yard strike into the roof of the net in front of a euphoric Gallowgate End, capping off one of Newcastle's most historic European nights.
The pair have played integral roles at the heart of United's defence during the last six seasons, partnering each other in the highs and lows of their Tyneside tenures but, on this occasion, it was a moment to savour in abundance.
"At 3-1, PSG had a couple of chances at that point so if they score, they always have the quality to get back into it, but we scored and then looking at the clock and realising there's not long left, all of my emotions came out," Lascelles admits. "It was an amazing and surreal moment.
"It could have been anybody who scored that goal but I was so pleased for Fabian. Me and him have been through thick and thin. We've been partners for a long time playing next to different people throughout the years. I was buzzing for him and the team."
Lascelles featured 11 times for United across all competitions during the 2022/23 campaign and has been required to bide his time to secure a starting XI spot of late following the impressive centre back partnership of Schär and Sven Botman.
Following the Dutchman's knee injury, Lascelles made his first competitive start since March in last month's Carabao Cup victory against Manchester City, the same opposition he faced six months prior, and recorded an admirable clean sheet in a valiant defensive display against last season's treble winners.
"I can honestly say I do everything I can in training, both on and off the pitch to be ready," says Lascelles, entering his eighth season as Magpies captain. "I know how football works but I think it's important that I know I'm always ready.
"I got asked to play and don't think I did myself any harm. It comes from the manager in the way we train, and our fitness levels have improved. It's not just me, with other lads stepping in and doing really well.
"Every footballer wants to play but at the same time, as much as I'm a real competitor and so hungry to play, I do understand how things work. You don't change what's not broken. If a team is winning games with a really good defensive record, that doesn't really get changed.
"I respect the manager's decisions and I want to do what is right for the badge. All I can do is work hard on myself and be ready when called upon. A few years ago, you may have taken your foot off the gas sometimes knowing you were going to play whereas now, you have to prepare for training.
"You have to do everything right, giving 110 per cent and proving yourself on the pitch. I think that's how it should always be as footballers. Just because you're a name or superstar signing, I don't think it matters. It's whoever performs and deserves the shirt."
During Newcastle's 2015/16 campaign, a season which involved relegation from the English top tier, Lascelles bravely criticised the squad's lack of leadership following a 3-1 defeat at Southampton, despite only competing in his maiden season at Premier League level.
It is a striking contrast to the "strong, tight-knit group" he finds himself amongst now, with a vast amount of squad members who have helped contribute, in their own right, towards a first top-four finish in two decades as well as ending a 24-year wait for a first domestic cup final appearance last season.
"I think how things are running at Newcastle works really well", he says. "We have a leadership group in myself, Kieran Trippier, Callum Wilson, Matt Ritchie and Dan Burn.
"We all chip in with different ideas and get together rather than it just being one person making the decisions for the whole team. Everybody knows their role and everyone is an important player in the group. There's no individuals. That's massive.
"I'm learning all the time from those boys as well. Matt Ritchie has tons of experience and is amazing with the younger lads. Callum Wilson is super professional, doing everything correctly, and leads by example along with Dan Burn and Kieran has all that experience and accolades during his career.
"I've been at the club for such a long time and know what things mean so when you combine the five, I think it's a really powerful thing and it works well together."
Despite a wealth of experience, racking up over 200 league outings for the Magpies, the 2023/24 season has proved a unique one for Lascelles and a number of his fellow teammates.
How has he found competing three times per week on a regular basis whilst juggling European football amongst league and cup fixtures?
"Since the takeover, things have happened really quickly. It's been a huge transition since the manager came in and we've all had to adapt very quickly which has been challenging.
"I think we're still all trying to find our feet with European football and the schedule. It's new to many of us but we're all sticking together as a group. The staff are fantastic and we all support each other so, collectively, we're in a good place."
The Derby-born defender, who celebrates his 30th birthday next month, joined United from Nottingham Forest in 2014 and made his 230th competitive appearance for United in their 2-2 draw at West Ham United.
Now with a more sagacious head on older shoulders, and over 300 club career appearances to his name, he admits his admiration for his game remains no different than during his grounding at Forest's youth system.
"Physically, I feel like the same person I was five or six years ago. I'd still say I'm a decent athlete. I look after myself and I think my game has improved.
"I'm a lot more calmer. I was a bit fiery and more emotional as a younger captain whereas now I think about things a little bit more. It's crazy how fast football can go.
"I love football and as long as my body can let me play, I would continue for as long as I could. Football is a short career so why not play for as long you can?
"It is most people's dream to be a professional footballer so I don't take it for granted because I know many would love to be in that position."
Now an older figure within a United squad blended with youth and experience, Lascelles reflected on past experiences as a fledgling defender at the City Ground which have led towards supporting the current crop of upcoming youngsters targeting a role in Newcastle's senior side.
"I remember being a young lad at Nottingham Forest looking up to the likes of Wes Morgan and Andy Reid in the dressing room", he says with a wry smile. "I'm probably that sort of person now!
"Whichever young lad comes into this group, whether it's Lewis Miley now or even when it was Sean (Longstaff) or Elliot Anderson, I like to make sure that it is comfortable for them because I know how important that is. It can be a scary thing training with the first team."
After heading into September's international break in uncharacteristic fashion, following a third successive Premier League defeat at the hands of Brighton & Hove Albion, the Magpies have responded terrifically with five wins in seven unbeaten fixtures in all competitions.
"We had a really tough start to the league, with some difficult fixtures. The way we bounced back from the Brighton defeat shows what we are about as a team.
"We are a resilient group and have been able to go on a good run, beating some of the best teams in the world. It's about being calm, trusting the process and working hard in training.
"We have a fantastic group, manager and staff who put so much time and effort into us all. You want to win every game but, sometimes, having a defeat can flick that switch. I think it's done that and it's now about making sure we remain consistent."
This interview was featured in Saturday's edition of UNITED, the club's official matchday programme, for the visit of Crystal Palace.
