The terrifying confrontation unfolded just before 5 p.m. Saturday at the chain's location inside the Roosevelt Mall on Cottman Avenue, according to a statement from the Philadelphia Police Department.
The store was closing its in-person service early because of staffing issues, but told customers it would still take online orders, police said.
Surveillance video showed the woman, in a gray top and pink pants, reach into her purse, pull a gun and gesture toward workers behind the counter.
The woman demanded to speak to the store's manager as a button was pushed to bring mall security to the scene, according to the police statement. An employee complied and made the woman's order "in an effort to have her leave," police said.
Even after completing the order, the woman pulled her gun again, police said. That is when she made her demand, took the meal and left, officials said.
Anyone who recognizes the woman is asked to call detectives at 215-686-3153.
This article was originally published on NBCNews.com.