He is planning to launch a site in the coastal town of Hythe, Kent, alongside his partner Alice Bussi.
Bussi is also stepping down from her role as food and beverage manager at The Seren Collection, which owns the Grove of Narbeth, for the project.
Barsby previously spent three years as head chef at two-Michelin-starred Gidleigh Park, cooking under Michael Caines.
He joined the Grove of Narberth in 2016, since when he has maintained its three-AA-rosette rating and was a semi-finalist for National Chef of the Year 2018.
Bussi launched the Beach House restaurant in Gower in 2016, before taking on the group management role.
Neil Kedward, managing director at The Seren Collection, says: “Hythe are blessed to have such a talented couple coming to their town to run what we know for sure will be a fabulous restaurant.”
The Seren Collection is now recruiting for a new executive head chef to take the reins at the hotel and restaurant.