[2] Larsen was raised in Cambridge, Massachusetts in a blended family of adopted children, from Cambodia, Vietnam, and America.

She has also performed in Avenue Q playing the role of Lucy the Slut/Kate Monster on National Tour, Broadway, and Off-Broadway.

In 2019, The Old Globe Theatre premiered the musical Almost Famous, based on the Cameron Crowe film of the same name, with additional music and lyrics by Tom Kitt, with Larsen starring as Elaine Miller (played by Frances McDormand in the film.

[7] Larsen is the founder of the Jaradoa Theatre Company, which combines performance with community service.

In 2009 a musical based on her own life, titled Shafrika: The White Girl, dealing with her experiences of living with a blended adoptive family, was staged at the Vineyard Theatre.