In early career, Vaughn has appeared in films Friday and Don't Be a Menace to South Central While Drinking Your Juice in the Hood. She co-starred opposite Joan Severance in the comedy-action film Black Scorpion (1995) and its sequel, Black Scorpion II: Aftershock (1997). Later in 1997, Vaughn was cast as high school secretary Lovita Alizé Jenkins-Robinson for the second season of The WB sitcom The Steve Harvey Show. She received three NAACP Image Award for Outstanding Supporting Actress in a Comedy Series for her performance on show. The series ended in 2002, and Vaughn later that year joined the cast of Showtime drama series Soul Food as Eva Holly. She received another NAACP Image Award for Outstanding Supporting Actress in a Drama Series nomination.

From 2003 to 2005, Vaughn was regular cast member on the UPN/The CW sitcom All of Us. In 2007, she had supporting role in the Tyler Perry's comedy-drama film Daddy's Little Girls opposite Gabrielle Union, and later had the regular role on another Perry's production, Meet the Browns (2009-2011). She also has appeared and produced number of low-profile movies in later years. She is owned production company called Nina Holiday Entertainment, that produced films such as Sugar Mommas, A Cross to Bear and Girlfriends' Getaway. In 2016, Vaughn has made her directing debut with comedy film #DigitalLivesMatter.

Vaughn grew up in San Francisco, California. She was married to Derrick Carolina and had a son, Daylen Ali (2001). She is currently married to former football player Karon Riley, and on April 21, 2008 the couple gave birth to a boy, Kal'El Joseph Riley. Vaughn established the non-profit "Take Wings Foundation," which provides scholarships, mentoring and job training opportunities for young women living in public housing in the San Francisco Bay Area.

In 2016, Vaughn was cast in the recurring role as housekeeper in Oprah Winfrey Network drama series, Greenleaf opposite Keith David and Lynn Whitfield.