"It's another crazy idea," the Oscar-winner, 38, says in the October issue of W magazine. "I just strapped those breasts down and went for it."
Blanchett adds: "If somebody challenges me to do something, I say okay. I say okay very quickly."
Such was the decision when she was approached by filmmaker Todd Haynes to play the famous (male) folksinger in the movie, which is due out in November. And despite – or, perhaps more likely, because of – the gender-bending, the director is pleased with the outcome, telling the magazine that Blanchett's look is "startlingly accurate."
Another challenge the actress says she's ready to face: more children. Blanchett, whose two sons, Dashiell, 5, and Roman, 3, are with her husband, writer Andrew Upton, says that when it comes to expanding the family, "We're not going to wait forever."
She adds, "God, I'd love it to be now. I'd love it to be next week."
This year, with son Dashiell starting school, Blanchett and Upton plan to settle in their native Australia, where together they will be co-directors of the Sydney Theatre Company. "He's five now," she says of her elder boy. "He needs to be settled and I respect that."
But the star says she is ready for a more structured existence. "In the past it's always been just whatever has come up, and then one thing leads to another," she says "Now, I'm going to have to plan things."
And though it will be a change of pace, as always Blanchett seems up for the challenge. "Believe it or not, I'm pretty good at just doing nothing," she insists. "I'm either sitting very still or running very fast."