Dr. Nancy Snyderman may have gone all home remedy to prevent Ebola ... because she may have made a very secret run Thursday to a New Jersey restaurant known for its soup ... thus violating her voluntary quarantine.

The NBC doc and her news team were placed on a 21-day voluntary quarantine as a precaution because one of the cameramen they worked with tested positive for Ebola.

But Snyderman reportedly violated the quarantine by going to the Peasant Grill in Hopewell Boro, New Jersey Thursday afternoon. Several people say they saw Snyderman in her Mercedes with shades and a ponytail as a man walked inside the restaurant to pick up some grub ... this according to Planet Princeton.

We're told the owners of the restaurant did not see Snyderman there.

The risk of Ebola for Snyderman and her crew is low ... nonetheless, the New Jersey Department of Health has now issued a mandatory quarantine for the group.

Someone connected to the restaurant tells TMZ ... the Peasant Grill is one of Nancy's favorite restaurants ... so much so she sometimes uses them to cater dinner parties.

NBC News will not discuss the matter, telling TMZ there are privacy concerns. We also left messages for Snyderman and her rep ... so far no response.