The fire broke out at 4.10am at Lewis’ Continental Kitchen on Curlewis Street.
Residents were evacuated and no one was injured.
The fire was put out by Fire and Rescue NSW crews.
This morning detectives removed a jerry can from the crime scene.
They say it was an “ongoing investigation with more questions than answers”.
Police are appealing for witnesses.
Anyone with information can contact Crime Stoppers on 1800 333 000.