The 23-year-old, who joined from West Ham United in 2013, completed his milestone during the 3-0 home win over Hartlepool United.
On reaching his ton, Mpanzu said: “I didn’t realise until Twitter people told me.
“I’ve been here three years now, so it’s good to get over the 100 mark and hopefully I can continue and make more appearances in the season.
“I think I could have had a lot more. Last season I had a lot of injuries, but now I’m fully fit and hopefully I’ll be making more appearances for Luton.”
Staying clear of injury has been a huge boon for Mpanzu this season as Tuesday night’s match was his 34th appearance this term and ninth 90 minutes in a row.
The previous two seasons have seen the midfielder restricted to 24 and 18 matches respectively, a number he has already flown past.
He put his renewed fitness down the backroom staff brought in by boss Nathan Jones, continuing: “Last season I had a reoccurring hamstring injury, so this season I’ve put a run of games together and hopefully I can keep that going.
“We’ve got a great man in Jared (Roberts-Smith, sport scientist) and our physiotherapist Simon (Parsell) who are just keeping everybody fit and ready to go.
“We’ve taken things step-by-step, having ice baths and recovering well, so it’s proving worthwhile with me and everyone else staying fit.
“We haven’t had any major injuries apart from a broken leg for Cam (Cameron McGeehan), but everyone has stayed fit and ready to go.”
Luton chief Nathan Jones credited his assistant Paul Hart for the work he has done with Mpanzu on the training ground this term as well, as on his impact, the midfielder said: “Harty is always in every day, getting on to us, saying: ‘how do you think you’re doing?’ And basically being a mentor to us.
“He makes sure we’re on our game in every single training session and making sure we’re at it on Saturdays.
“It’s more concentration for me too. The gaffer has said it, so he’s drilled that into me and it’s proving worthwhile with the performances I’ve been putting in recently.”
One thing Mpanzu is now looking to add to his game is goals though, with his last against Dagenham on April 12, some 39 matches ago.
It has become harder playing in a more deeper role than he has been used to, although the ex-Hammer has shownhis creative side in recent games, setting up both Isaac Vassell and Danny Hylton to score.
He said: “I haven’t got any goals this season but I’m creating more for other people. Hopefully I can get some goals in the games coming.
“The gaffer keeps getting on to me about scoring more goals but, obviously, I play defensive midfielder, so it’s harder. But now I’m getting into the box more and I just need to add goals
“I’d like people to assist me so I can get some goals, but if I have to assist the team and we win then I’m not bothered if I score or not.
“As long as we get three points or we go through in the cup then I’m happy either way.”
Meanwhile, although only being at the club for a short while, team-mate Luke Gambin has been mightily impressed with Mpanzu’s performances.
He added: “or me he’s brilliant, just a powerhouse isn’t he? Some of the situations, even when I’m playing, I’m like, how’s he going to get out of there? Then his legs start moving and you’re like, ‘oh, better start running with him.’ He’s a brilliant athlete and a really good technical footballer.
“He believes in his ability, you see him go past players like it’s easy. He’s strong, a great lad too, so well done for him for his 100th appearance, congratulations to him.”