"'Turandot' has always been a role that intrigued me, and I thought about it. People asked me to sing it, and I turned it down in a couple of places," she told AFP.
The Met in New York was among those asking. "But I thought that if I did a production that was an old production, I wouldn't get the proper amount of rehearsal time. It is daunting on many levels.
"But I do feel, now, that I want to give it a try."
Brewer takes to the stage for the first time Sunday as the terrible "ice princess" who methodically executes those who seek her hand in marriage and are unable to answer the three riddles she poses.
She will be accompanied by the Los Angeles Philharmonic orchestra under the baton of its charismatic principal conductor, Venezuelan Gustavo Dudamel.
The role has been taken up by some of the top singers of the 20th century, from Maria Callas and Birgit Nilsson to Joan Sutherland and Montserrat Caballe.
"I've been working on it for a couple of years, slowing getting the character into my body, my mind, my voice," Brewer said.
"Many times Turandot is one-dimensional: she is just the angry and cruel ice princess... to make believable that she and Calaf can have a relationship... you have to start catching glimpses of who she is as a human being.
"I have to have this very lyrical approach so I can avoid the temptation to scream or make the role so harsh," she added.
Brewer says that she can add the Puccini role to her repertoire now in large part because of her patience and the caution which has been a hallmark of her career. "I've had an unusual journey in my career," she said.
"Thankfully I always had people just advising me and saying: 'You know, you sing Mozart so beautifully now, why don't you take advantage and sing that as much as you can?' Then, gradually, we'll do some of the Richard Strauss.'
"I didn't sing Wagner until I was 40. I always looked at sort of the big picture and said OK, in ten years I would like to be singing this, in 15 years, I would like to be singing this," she added.
"But I think that in the long run, and I tell this to my students, if you can be patient and if you can say no to the bigger things early in your career, you can be singing and you should be singing in a healthy way until you're 60."
One of her biggest influences was the legendary Swedish soprano Birgit Nilsson, whose voice was so powerful that "Turandot" seemed like a bracing walk for her.
It was Nilsson who advised Brewer to wait before singing the ice princess.
"I was 30 years old then, and she was absolutely right. So often we would work on something and she would say: 'Well, you know, I've sung this role, but I think you will sing it more beautifully.
"'You have a more beautiful instrument than I, but I think I have a stronger instrument.' That's why at that time, she said: 'Keep singing Mozart.' It was the exact advice I needed to hear."
She added: "I took the advice. I turned down all those offers and now, as I've matured and I feel that my voice is stronger, I wish she was still alive so she could hear it.
"I think she would be happy to know that I'm doing it now."
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