The incident occurred in the High Street on the evening of Friday 12 November.
Police are appealing for witnesses to come forward.
A man has been arrested as part of the investigation.
Officers investigating a report of a racially aggravated public order offence in Potters Bar are appealing for witnesses to come forward.
The incident occurred in the High Street, at around 6.55pm on Friday 12 November.
A woman was getting into her car, which was parked near Pizza Di-Napoli, when a man allegedly shouted offensive and racially offensive language towards her, before throwing food onto her windscreen.
He then drove off in a white van.
PC Nikki Daniels, who is investigating, said: “It is believed there were a number of people around at the time who may have seen what happened. As part of our ongoing enquiries into the incident, we’re appealing for any witnesses to please come forward. Did you see the incident take place? Or did you see those involved prior to it? If you have any information at all, we’d like to hear from you.”
Anyone with information is asked to please contact PC Daniels via email.
You can also report information online, speak to an operator in our Force Communications Room via our online web chat or call the non-emergency number 101, quoting crime reference 41/88680/21.
Alternatively, you can stay 100% anonymous by contacting the independent charity Crimestoppers on 0800 555 111 or via their untraceable online form (opens in a new window).
Hertfordshire Constabulary takes incidents of hate crime seriously. If you have been a victim, please report it. Specialist officers are on hand to provide support.
A 26-year-old man has been arrested in connection with the incident and released under investigation while enquiries continue.