Blanchett, attends the opening night celebration for 'Streetcar Named Desire' in New York, looking luminous despite a grueling rehearsal schedule and tending to her three young boys, who are staying with her. Photo: Getty Images

Cate Blanchett is one of those celebrities who defy all beauty rules. She always appears luminous, even though she should not have the time -- or the energy -- to look as good as she does.

At 40, Blanchett has three young boys, a busy film career, and is currently touring with the Sydney Theater Company, for which she's the co-artistic director with her husband, Australian playwright Andrew Upton. Blanchett is starring in one of the most emotionally taxing theater roles ever written, as the tragically idealistic Blanche DuBois in Tennessee Williams' 1947 Pulitzer-prize winning masterpiece, "A Streetcar Named Desire."

"I don't think my skin has ever had so much abuse as it's had in the last 3 months," Blanchett told us.

But she doesn't look a day worse for the wear. We know, because we had the pleasure of interviewing Blanchett face-to-face in a very sunny hotel room in New York City, shortly after seeing her in "A Streetcar Named Desire," which is playing a sold-out run in New York.

When pressed on her on beauty secrets, Blanchett pegs her good skin fortunes to her religious use of the skincare line SK-II, for which she's been the international spokesperson for the past four years. "I think I would be on the floor if it wasn't for this stuff," she says. "It's a good friend in that way."

The pairing initially surprised the cosmetics industry (or us, at least) because, frankly, Blanchett didn't strike us as the type to front a beauty brand. But, in one of those match-made-in-heaven scenarios, she became addicted to SK-II well before she landed on their payroll – Blanchett began using the brand nine years ago, during her first pregnancy.

"A friend of mine noticed that there were changes happening to my skin -- I became really dehydrated and started getting some discoloration," says Blanchett. "She suggested I use SK-II Facial Treatment Essence and SK-II Whitening Source Clear Lotion. I used it for the rest of the pregnancy, and obviously continued after having a baby."

Blanchett poses for SK-II in an advertisement for their new moisturizer, Skin Signature Cream. Photo: Courtesy of SK-II

Like any woman enamored with her skin care, Blanchett knows her stuff. After schooling us on the efficacy of SK-II's star ingredient, Pitera -- which is distilled during the sake making process and responsible for the celestial nickname of "holy water" given by Japanese fans to the brand's star product, Facial Treatment Essence -- Blanchett deadpans. "It kind of is. I'd drink it if I could."

Below, Blanchett shares more of her beauty likes (served up with a wry sense of humor), as she dishes on her love for bronzer, her favorite naughtily-named blush, her brief "goth" period, and what it's like to wear zero makeup on stage in front of a sold out audience (um, eek).

Blanchett backstage with Armani at his Spring 2010 runway show in Milan. Photo: Getty Images

What has been your favorite movie look? What character made you feel really beautiful?
Blanchett: I was in "Life Aquatic," the Wes Anderson film, and I was quite tanned, which is really unusual for me. I quite liked having better color, because I'm ordinarily so pale.

StyleList: But you grew up and live in Australia, which is the number one country for skin cancer?
Blanchett: The sun is so strong. I've had to stay out of the sun because I just burn.

StyleList: Which really may have been the best thing for you, right?
Blanchett: Exactly. Well you obviously need a little bit of sun for vitamin D, but two of my sons have quite pale skin like me, so I'm really conscious of the sun. Apart from the risk of melanoma, it does so much damage to your skin.

StyleList: So is bronzer a must in your makeup routine?
Blanchett: I tend to wear a few bronzers. For blush, Nars has a really good shade called Deep Throat. I picked it up and was like, "I have to buy that because of the name!" I also love Chanel's Les 4 Ombres De Chanel eye shadows – they're good.

StyleList: You are a busy mom so what are the things you do to maintain your sense of self?
Blanchett: Like most working mothers, time is sacred. All I can manage is five minutes in the morning and evening to care for my skin, but I'm quite religious about it. It makes me feel good to have that little sanctuary for five minutes – every other day I stick an SK-II Eye Mask in the freezer and put that on, and it helps.

StyleList: What are you favorite skincare products?
Blanchett: If I were on a desert island, I'd take SK-II Facial Treatment Essence and Skin Signature Cream moisturizer. It's olive oil based, so it's really light and you never feel gunky. Your skin stays hydrated, whether you're flying, in the cold weather, or constantly taking makeup on and off. It raises your skin's ability to tolerate abuse. And frankly, I don't think my skin has ever had so much abuse as it's had in the last 3 months.

Blanchett's desert-island skincare picks: SK-II Skin Signature Cream and Facial Treatment Essence. Photo: Courtesy of SK-II

StyleList: What products do you always have in your bag?
Blanchett: I've got a travel pack of SK-II Facial Treatment Essence, which I often put on during the day, and I've got a tube of Lucas Papaw Ointment. Papaw is a great healer of the skin -- perfect for when you've got a burn or a scrape, which kids often have, and it's good for your lips, too. My friends in America are always asking me to bring it over.

StyleList: What is your typical beauty routine?
Blanchett: Wake up, having not had enough sleep, I'll put on SK-II Facial Treatment Essence and their Cell Luminescence [available in the US starting this spring], which is great stuff, and then I'll moisturize with Skin Signature Cream and put on sun protection on top of that.

StyleList: How has your skincare routine changed over time?
Blanchett: Back then, I'd go to bed with my makeup on if I'd been out. And I went through a big gothic phase, so my pillow was always covered in black mascara and white pancake makeup.

Blanchett with son Ignatius in April 2008, shortly after he was born. Photo: Getty Images

I always wish I'd been cool enough to be goth.
Blanchett: Well, it's not that cool in retrospect, and I'm definitely more careful now about removing it. Also, my linen is nicer than it was before and I don't want to ruin it.

StyleList: What do you want for the holidays?
Blanchett: I want a set of hot rollers for Christmas. I've never had one and I'd really like a set of hot rollers!

StyleList: And do you have a New Years resolution?
Blanchett: When I was doing "Street Car" in Sydney, because we were home, I started going to the gym twice a week, which is very big for me. I kept each session to 45 minutes -- something small and manageable. It's something I'd like to keep doing, but obviously while I'm on tour that's a bit impossible, especially since I've got the 3 kids in the hotel with me! But there is something about making that commitment, which is my New Years resolution. I'm not going to give that up.

StyleList: In "A Street Car Named Desire," your character Blanche DuBois' sanity unravels before our eyes. And her look changes too: She starts off pert and powdered, then paints on exaggerated red lipstick, and ends up barefaced. How did you use beauty throughout the play to round out your role?
Blanchett: Blanche is incredibly concerned about externals, because she is trying desperately to keep this dark mess that's welling within her from spilling out. Whenever people talk about people they find beautiful, they talk about an inner light within them -- what's going on internally will always express itself externally. And Blanche is terrified of that.

In the play, she talks about her age a lot; it's a big concern for her. But in reality, Tennessee Williams is referring to the weariness in the age of her soul, as much as he is about her physicality. The character he wrote was actually in her early 30's, so I'm probably already too old to play the role. But it's a role traditionally played on the stage by an actress in her 50s or 60s.

I did think a lot about ways that we try and hide from who we are externally. In the play, I end up with no makeup on at all. Backstage, I wipe the makeup off.

Blanchett as Blanche Dubois in "A Streetcar Named Desire." Photo: Lisa Tomasetti , AP Photo/BAM

StyleList: It is so courageous to come out without any makeup on. Did you cheat it -- was anything on your face?
Blanchett: Just SK II Essence, and Eye Cream. And that's it.

StyleList: Is it scary for you to do that, or as an actress is it something you are used to?
Blanchett: The first time I did it I thought, "I'll just put a little bit of concealer on" and then I thought, "Why am I doing that?" Either you do it or don't do it. If you think of where Blanche is at the beginning of the play, constantly powdering and covering up, it's the most extreme difference.

StyleList: Your roles through the years have been so different. What from a beauty perspective, has been the farthest reach out of your comfort zone?
Blanchett: I'd say playing a version of Bob Dylan in "I'm Not There" because you were going against everything that you would ordinarily do as an actress on film. You know, you wanted to make your skin look rough, blotchy and course, rather than smooth. It was a real challenge and I found that utterly liberating. And that's great.