Why Zac Posen Thinks About Kim Kardashian Each Morning

Zac Posen knows women.

The famed designer's strong feminine aesthetic is a favorite among A-listers, who sashay down red carpets in his form-enhancing frocks. On "Project Runway," he's surrounded by women at the judge's table. Tonight's Season 12 finale sees guest fashionista Kerry Washington joining him — along with Heidi Klum and Nina Garcia — as they crown a winner.

[Related: Behind the Seams at the 'Project Runway' Finale: Who Will Win Big? Who's a Sore Loser?]

"Nobody ever really talks about how rigorous the challenges are. It is very real-deal to conceptualize and make something in 24 hours," Posen, who knows a little something-something about fashion, says to omg! about the reality competition. "It's actually unheard of. I mean, there are no, like, hidden elf sewers in the basement of Parsons [The New School for Design]. The contestants are cutting and sewing and making that stuff themselves and that's really impressive."

Impressive is Posen's own resume, dressing everyone from the first lady (who is a huge fans of his knits, something he describes as "amazing") to the queen of talk, Oprah Winfrey (whom he did a fitting with over Skype, which he wouldn't do with just anyone). So we ask him about a few famous femmes in his orbit…

1. He thinks about Kim Kardashian each morning. While discussing how the new mom was bashed for her maternity style, Posen says, "I say she and her whole family can laugh all the way to the bank. They get pop culture. And there are so many sort of cliché phrases, but I think that the more outrage that's created, the more demand there is for them."

"I've worked with Kim and she is one of the loveliest, sweetest women to work with," he continues. "She writes the most polite thank-you notes. Every morning I wake up to a really beautiful, small bedside Hermès clock and I think: How chic and lovely of Kim Kardashian. It was a thank-you gift."

2. He went from being Lena Dunham's babysitter to her designer. Growing up in New York City, Posen babysat for the "Girls" actress, taking her on the subway each day to school in Brooklyn. "Was I good babysitter? I hope so," he says. "I was definitely a fun babysitter. It's funny, [in a recent article] she talked about sort of the nurturing role [I had in her life], but she was a very inspiring young girl."

And what is it like to dress her now — like he did for the 2013 Golden Globes? "It's wonderful and incredibly gratifying. I always want Lena to feel as confident and smart [as possible]," he says. "It's the beginning of a great artistic career that I'm sure is going to surprise everybody as it evolves."

3. He once had Ashley Olsen as an intern but did not make her get him coffee. "No, she didn’t get me coffee, I don't believe," he says of the "Full House" star turned designer, who interned for him in 2005. "She was a great intern. She worked in multiple departments. She was driven. She was poised. She had great style. She liked great fashion. She was lovely."

And no different than the rest of the aspiring designers.

"She was treated with great respect, as we treat any of our interns, but on an even playing field," Posen adds. "And I think she was very happy about that."

4. He made a $1.5 million, 24-carat gold dress for Caroline Correa. That gold dress the Brazilian actress and model slinks around in in those Magnum ice cream ads? That's a Posen original. "It took months to make, from conception to final, and there were definitely hurdles and challenges," he admits. "It had this all-over shimmering texture, but then also highlighted and accentuated the curves and sensuality of a woman's body and gave the same experience to the wearer as the experience of indulging in the Magnum Gold ice cream bar."

5. No big surprise here: He loves Heidi. "Heidi Klum is one of the most beautiful, poised women I know in the world," he smiles. And he's loved working with her as well as Nina and show mentor Tim Gunn the last two seasons of "Project Runway."

"What's wonderful is that we actually get very invested into the show," he says, "and really care about giving the right guidance and making the right decisions."

See what their decision for Season 12 is when the finale airs tonight on Lifetime.