Thanks to a starring role on the addictive Gossip Girl, a new movie, and a high-profile romance, she’s Hollywood’s proverbial It Girl. One more thing: You know you love her.

Blake Lively is starving. She slides into a booth at a charming restaurant in New York City’s West Village and immediately buries her head in the menu. “Let’s share a bunch of stuff,” she says, then adds, “On average, I order about three meals for myself in one sitting.” She isn’t kidding. Two bread baskets, two appetizers, two pasta entrées, and three desserts later, she decides that’s enough food…to start with.

But there’s good reason for Blake’s ravenous appetite. As one of the breakout stars of television’s most buzzed-about show, Gossip Girl, she’s spent the last several months working 18-hour days. And that’s in addition to promoting her new flick, The Sisterhood of the Traveling Pants 2, in which she plays a college student coming to terms with her mother’s death. Though she looks every bit the chosen Hollywood starlet (she’s dressed in skinny jeans, black ballet flats, and a leather bomber jacket), she hardly acts it. “I don’t drink. I don’t do drugs. But I do sleep around a lot,” she deadpans, before busting into laughter.

The fact is, her own high school experience in Burbank, California, was a far cry from her character’s ultraprivileged existence. While Serena van der Woodsen spends her time sipping champagne at the Palace Hotel dressed in designer clothes, Blake, now 21, was more of a gung-ho overachiever. “I was class president, on the cheerleading squad, in a competitive show choir, and in, like, six different clubs,” she says. She even sported a bulldog costume to act as mascot for some football games. That up-for-anything attitude is what helped her break into acting. She got her first gig (in the original Sisterhood movie) because her brother, also an actor, thought she would like performing and asked his agent to send her on a couple auditions.

On being nothing like her on-scre­en persona Serena van der Woodsen: “I was class president, on the cheerleading squad, in a competitive show choir, and in, like, six different clubs.”

On what she sees in a boyfriend: “I don’t want to date someone just to date someone. I want to be with a guy who’s going to be better my quality of life, better me.”

On kissing and telling: “I’ve kissed just three people, other than stuff I’ve done for TV or movies. I know — I’m weird.” ­

On her steady relationship with costar Penn Badgley: “I hope Brad Pitt doesn’t hear this. He’s never going to want to marry me.”