You have worn some gorgeous looks today, Nicole. Can you talk us through them?

“This pale pink dress is soft and beautiful and ethereal and was inspired by a look that I wore to the Pride of Britain Awards recently. I’ve also worn the most gorgeous yummy cashmere sweater with big sleeves that you just want to snuggle up in, then a very simple and elegant velvet slip dress.”

Do you enjoy photoshoots?

“I do, but my secret is music – I have to have great music and it has to be the right music for the right vibe of the shoot. Today there was a lot of Beyoncé; it’s all about [her album] Lemonade.”

You invited us behind the scenes of today’s photoshoot to celebrate being the new face, hair and nails of Perfectil supplements. How long have you been taking them?

“I’ve been taking Perfectil for a few years now. They are my favourite beauty supplements and I find that they help my nails, hair and skin, especially when I am really busy.”

Your hair, skin and nails seem so perfect that I’m surprised you feel the need to take a beauty supplement…

“Oh thank you, but trust me – this is hours of glam and beauty. For me, Perfectil is part of the overall wellbeing. I think beauty comes from within, it’s part of how we sleep and eat well, exercise and just look after ourselves. Even when I am working super hard and not having much sleep, like right now with X Factor, I still drink lots of water and exercise – anything that I can get my beat on to keeps me energised.”

You have gorgeous hair and it’s all yours – no extensions. What’s your secret?

“Perfectil for hair, obviously, but I do use clip-in hairpieces for the show or the red carpet, but yes, today this is all mine. But my secret is Olaplax [a hair repair treatment]; it really works. And I also like Oribe texturising sprays and I always use a heat protector spray.”

What are your favourite beauty treatments?

“A deep-tissue massage is my all-time favourite. But also any type of facial, particularly the collagen wave facial – it’s awesome.”

What would I always find in your make-up bag?

“A grapefruit hand sanitiser and coconut oil because that’s my multi-purpose beauty balm for everything. For make-up at the moment, my two favourite brands are Charlotte Tilbury and Tom Ford. In fact, Charlotte is winning right now – I love Charlotte Tilbury lipstick and her new eyebrow colour gel. And Giorgio Armani new Lip Magnets are amazing. Oh, and Tom Ford Shade & Illuminate contouring palette. And I love my friend Tyra Banks’s contour sticks; they are like crayons you just draw on your face and are really great, but you guys don’t have it yet – Tyra you need to bring it to the UK.”

Charlotte Tilbury reads hello!, so I think we need to get her to create a Nicole Hot Lips colour just for you…

“Oooh yes, hi Charlotte!” [Blows kisses].

Do you have secrets from The X Factor that you can share?

“They are live shows so anything can happen at any moment. I am obviously rooting for my boys; they have the best mentor.”

It’s been a very contentious and controversial series. Why do you think that is?

“Because Simon Cowell is back – he loves to grab the headlines.”

Last time we met, you were talking about this amazing cycling class in the US called SoulCycle and how we need it here. Now you are back and it is here, have you taken any UK classes?

“You’re welcome UK and where’s my commission? In fact, I’m still waiting on my One Direction commission [Laughs]. But no, I haven’t had the time and now my favourite class is called Twerk Before Work – I kid you not. It’s a dance cardio class and it’s like you are at a club but it’s 8am and you are getting in a really strong workout. I like to change it up when it comes to my workouts. I jog, listen to music, zone out during exercise. Before my shoot today I did some Bikram yoga – I love to get a good sweat on.”

Are you enjoying your time in London or are you missing Los Angeles?

“I am living in London and enjoying it, but I’m not going to lie – I have been very, very busy and this city has been keeping me going. I come over every year to do X Factor for three months and I rarely fly out, so I must admit that I’m a little homesick and am looking forward to Christmas now. But I’m grateful.”

Describe your perfect Christmas day…

“I love a white Christmas in the snow, but this year I shall be in Hawaii and so this Christmas day will be a walk on the beach, going to church – my poppa is a bishop so we all go to mass as a family – and just relaxing. We have a huge feast at lunch, then we play cards and games and hang out and not do much, then eat again. I’ll maybe go for a swim in the ocean and roll around in the sand with my nieces, who are six and seven – that’s definitely on my Christmas wish list.”

Your nieces are the perfect age for Christmas and Santa Claus. Dot hey believe in him?

“Of course they do. I always spend my Christmas with them and they make it – they really do.”

What’s your signature scent

“Byredo La Tulipe. But I also love anything with Hawaiian flowers in it because it reminds me of my childhood and growing up.”

What’s your favourite piece of beauty advice?

“Smile.”

Is it true you drink coconut oil in your coffee?

“Oh yes. I want to have my own coconut oil; I use it for my hair, my skin and my deodorant and I eat it every day.”

Are you comfortable doing your own hair and make-up on days you’re not working?

“A lot of people like to do their own make-up and hair, but that’s not me, so I keep it simple. I like hats and use a flat iron, super-light make-up and I always put a lip on.”

Who is your beauty icon?

“I love Sophia Loren and Brigitte Bardot. And JLo, of course, and Gwen Stefani for fashion.”

What’s next for you after X Factor?

“I’m working on a project that could be mega and I’m really excited about it. It’s music, but that’s all I can say.”

We hear you are appearing in two films too…

“Yes. I’ve just shot my first lead in a movie, a re-imagining of Dirty Dancing, which comes out next year. I play Penny, Johnny’s dance partner, Abigail Breslin is playing Baby and Colt Prattes is Johnny. It’s being released to celebrate the 30th birthday of the original.”

And you are voicing a Disney character too…

“It’s a Disney animation film set in Polynesia called Moana and I’m really proud to be in it because of my Hawaiian heritage. It’s about a little girl called Moana and I play her mother. Let’s just say that it’s been a very busy year for me and I feel blessed.”