Beyonce Knowles said she gained 15 pounds to play legendary singer Etta James in the upcoming movie "Cadillac Records."

Knowles told In Style magazine that it was "way easier and tastier" gaining weight than having to drop pounds to star in "Dreamgirls."

Due in theaters Dec. 5, "Cadillac Records" chronicles the rise and fall of R&B label Chess Records.

The film also stars Adrien Brody as Leonard Chess, Jeffrey Wright as Muddy Waters and Mos Def as Chuck Berry.

Knowles, who recently confirmed her marriage to rapper Jay-Z six months after tying the knot, also told the magazine that she was "terrified, but excited" to take this big step.

She told In Style that she feels like a "new woman" now that she's married.