2016–present: Career expansion
On February 1, 2016, it was announced that Ashford would play the role of Columbia in the FOX television remake The Rocky Horror Picture Show: Let's Do the Time Warp Again. Ashford starred alongside Laverne Cox, Victoria Justice, and Ryan McCartan.
On July 14, 2016, it was announced that Ashford would be starring opposite Jake Gyllenhaal in New York City Center's three October concert performances of Sunday in the Park with George as Dot/Marie, a role originated by Bernadette Peters on Broadway. On December 13, 2016, it was announced that Ashford would reprise her role as Dot/Marie opposite Gyllenhaal in Sunday in the Park with George in the show's Broadway 10-week revival at the Hudson Theater. Ashford was not eligible for a Tony Award for this performance, as the production withdrew itself from any award competition, including the Tony Awards. A statement was released on February 3, 2017, saying: "The producers of Sunday in the Park with George will not be submitting Hudson Theatre’s engagement of this New York City Center production for awards eligibility. With a season so full of tremendous, soon-to-be long-running new musicals and revivals, the producers feel this extremely limited, special run stands most appropriately outside of any awards competition. The production is nevertheless proud to be part of such a landmark Broadway season."
David Rooney of The Hollywood Reporter praised her work writing, "Ashford is the funniest Dot in memory", noting "her mischievous humor and openness [plays] a delicate counterpoint to Gyllenhaal’s Seurat...But there are tremendously moving layers to her characterization too, revealing the searing wound beneath the pride" Marilyn Stasio of Variety also praised Ashford writing that she has a "stunning voice and [was] quite enchanting". In 2017 the cast album was released by Warner Music Group. It was produced and mixed by Bart Migal and features the full Broadway company, including Jake Gyllenhaal, Robert Sean Leonard, Erin Davie, and Penny Fuller.
On April 4, 2017, it was announced that Ashford would be joining The Public Theater's Shakespeare in the Park production of A Midsummer Night's Dream as Helena. The production also co-starred Phylicia Rashad as Titania, Kristine Nielsen as Puck and Danny Burstein as Nick Bottom. The production received mixed responses but Ashford was praised. Elizabeth Vincentelli of Newsday wrote, "[Ashford] has emerged as a sublimely gifted comedienne. She [has] impeccable timing with delightfully unexpected line readings."
On September 12, 2017, it was announced that Ashford would join the cast of Woody Allen's drama film A Rainy Day in New York, which was completed on October 23, 2017. The film was released in Europe, Asia, Central America, and South America in 2019 and in the UK and US in 2020. On November 3, 2017, it was announced that Ashford would make her New York Philharmonic debut in a televised New Year's Eve concert celebrating the music of Leonard Bernstein. Also featuring Laura Osnes, Aaron Tveit, and Christopher Jackson, New Year’s Eve: Bernstein on Broadway featured songs from Bernstein's scores for On the Town, West Side Story, Candide, and Wonderful Town. It was accompanied by Bramwell Tovey and aired on PBS on December 31, 2017.
Ashford appeared as Elizabeth Cote in four episodes of the mini-series The Assassination of Gianni Versace: American Crime Story, which premiered on January 17, 2018. On February 15, 2018, it was announced that Ashford would lead a single-camera comedy pilot Southern Hospitality for ABC. Tristram Shapeero was set to direct. The pilot was not picked up. Ashford co-starred in the Jennifer Lopez-led comedy film Second Act as Hildy, opposite Vanessa Hudgens. The film was released in 2018. On July 23, 2018, it was announced that Ashford would be starring in American Reject, a new musical film. Ashford was set to reprise her role as Dot/Marie in Sunday in the Park with George at the Savoy Theatre in London in 2020. However, due to the COVID-19 pandemic, the run was postponed to 2021. In February 2020, Ashford was cast as one of the two main lead roles for the CBS situation comedy B Positive, in which she plays Gina, an unstable woman who is the perfect match for a person in need of a kidney, who happens to be a divorced father who she knows from the past. For its second season, the series was revamped and centered on Ashford's character. Ashford also performed the series' lengthy opening theme in a musical-theater style. The final episode aired March 10, 2022. The series was greenlit by CBS on May 8, 2020, as an entry in the 2020–21 television season.
In 2021 she played Paula Jones in the Ryan Murphy limited drama series American Crime Story: Impeachment on FX. The role, a departure from her comedic roles, was a serious one that demanded a physical transformation. Ashford did not meet with the real-life figure but heavily relied on the wealth of material available. She said "I can have empathy for the fact that she came from a very conservative family...I also have a great deal of empathy for the way the media treated her and the way she was seduced by right-wing operatives to make certain choices at the same time." The following year she played Irene in the Hulu limited series Welcome to Chippendales. She starred alongside Kumail Nanjiani, Murray Bartlett, and Juliette Lewis.
In 2023, she returned to Broadway in the revival of Stephen Sondheim's Sweeney Todd: The Demon Barber of Fleet Street taking on the role of Mrs. Lovett opposite Josh Groban as the titular character. She earned rave reviews for her performance, including praise of her vocal abilities and her comedic timing, with many stating she made the role her own and distinguished herself from Angela Lansbury who originated the role. She received her third Tony Award nomination, this time for Best Actress in a Musical. She also earned her first Grammy Award nomination for Best Musical Theater Album for her performance on the cast album. It was announced on October 14, 2023, that Ashford's final performance as Mrs. Lovett would be on January 14, 2024. Later that month, it was announced that Sutton Foster would succeed Ashford as Mrs. Lovett starting on February 9, 2024.
