Cambridgeshire Live reports the chef will take the reins at Thirsty & Hungry, ahead of plans to open his own restaurant in the city centre.
Poynton will serve a lunch menu of sandwiches, food to-go, sharing plates and lighter dishes.
The café will open from 10am seven days a week, before turning in to a bar serving wines and craft beer in the evening.
Poynton told the paper the role was a chance for him to ‘do something completely different’.
It follows his departure from Cambridge restaurant Alimentum this summer after a decade in the kitchen.
He joined the restaurant in 2009 from Daniel Clifford’s Midsummer House and held a Michelin star there for five years, before losing it in the 2018 edition of the guide.
Alimentum announced its shock closure in October, months after Poynton's departure.
Thirsty & Hungry is the brainchild of the team behind bar and bottle shop Thirsty Cambridge.