American Idol judge, Mariah Carey took the stage last night during the show's 12th season finale. 

The pop diva dawned a white mermaid gown and belted out hit after hit. Starting with her 1990 debut single, "Vision of Love" she continued on to "Make It Happen," "Hero," "We Belong Together," and ended it with her latest, "#Beautiful."

Despite her beautiful performance, articles have surfaced referencing Twitter uproars that the singer and judge was lip-syncing.

But is it that the notes come so naturally that people were tricked into believing it was lip-synced OR did she really do it? 

Check out the video from last night's finale and tell us what you think!