The 56-year-old also shared another photo of her stunning new look to her Instagram Stories, and tagged Fearless Productions, which we can assume she's been working with for her latest gig.
Her followers were quick to flock to the comments to share praise on her new look, and their excitement to meet her new character.
"Looks interesting," one user wrote, while another said: "Ohh so excited to hear this." Others shared their love for her latest transformation, with one user writing: "Beautiful colour."
While we wait for more details on her exciting new project, we can watch Rebecca continue to impress in the Celebrity MasterChef kitchen.
The actress joins several other Aussie celebs in the competition, and recently penned a sweet message about her time on the show.
"This time next Sunday I walk through the famous Masterchef doors with these glorious humans," she said ahead of the show's premiere.
"None of us knew what we were getting ourselves in to and I am so so grateful to each and every one of them for the hugs, the laughs, the tears and the joy."
She went on to add: "They are all incredibly open hearted funny kind beautiful people and I can’t wait to relive what was truly one of the most extraordinary experiences of my life (for a whole bunch of reasons!)."
In the post, Rebecca shared several behind-the-scenes snaps with her MasterChef co-stars, including Tilly Ramsay, Chrissie Swan, Dilruk Jayasinha, Archie Thompson and Collette Dinnigan.
You can keep up with Rebecca's cooking journey when the show airs on Sunday and Monday nights on Channel 10 and 10Play at 7:30pm.