The legendary screen star won a Best Actress Academy Award for her turn as the long-suffering mother in the 1945 movie, based on the novel of the same name by James M. Cain.
WInslet is set to bring the character back to life in a new TV series, and admits she only saw five minutes of Crawford's film before turning it off.
She explains, "When you're playing Mildred Pierce and you know someone utterly extraordinary has played it before, it's a fine line. What do you do?... I saw the first five minutes, and I thought, 'You know what? I shouldn't see this. Because I wouldn't be able to unsee it.'
"I could feel almost immediately watching Joan Crawford's brilliant performance that what I was working toward with Todd (Haynes, director) was just something different. Not better, cleverer or any of that. It was just a different character. And I knew I had to hang on to that."