Kristen Schaal (born January 24, 1978) is an American actress, writer and comedian, best known for her roles as Mel in the HBO series Flight of the Conchords, as Louise in Bob's Burgers, as Frantic Spectator / Old Ryan's Wife in Xavier: Renegade Angel, as Hazel Wassername in 30 Rock, and as a contributor on The Daily Show. She now stars in Disney Channel's Gravity Falls, in which she voices Mabel.