Below you can check out a reported audition tape for The Flash TV series featuring an actress playing the role of Iris West with the other lady off-camera voicing Barry Allen.
More than likely the dialogue used is just for the scene and won't be a part of any actual episode.
A previous leaked character description for Iris West and Detective West described the characters as African-American.
IRIS - 22-28 - African-American - As smart as she is beautiful, Iris is in grad school studying psychology. She's also Barry's mile a minute, fast-talking, quick-witted best friend. Her father, Detective West, took in Barry when his mother was murdered, and his father was wrongly accused and imprisoned for her murder. In a tough childhood for Barry, she was the one "not tough" thing. She's unaware of Barry's strong feelings for her.