It happened at Fuzzy's Taco Shop at 5am on Sunday.
Investigators say the fact the restaurant was closed at the time of the fire, is one of the reasons they find it suspicious.
Witnesses captured video of huge flames shooting from the building.
"I saw flames shooting out the windows and the side of the building here and into the street and smoke billowing out," said witness Brian Hinchmarch.
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Brian Hinchmarch lives less than 50 feet from Fuzzy's Taco Shop.
He's grateful the fire didn't spread to his home.
Blanca Torres works at Fuzzy's Taco Shop and arrived to find the place on fire when opening the store Sunday morning.
"They didn't even make it a year. January 1st they opened," said Blanca Torres.
Torres started working at the restaurant four months ago. Now as a single mom of two, she's left looking for a job just days before Thanksgiving.
"I'm a single mom of two. Their birthdays are next month. Christmas this month coming and Thanksgiving this week," said Torres.
Torres has a boy who's about to turn one and a four-year-old daughter.
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"You have no money coming in. You have to start all over," said Torres.
Meanwhile, arson is continuing to investigate the fire. They're reviewing surveillance video and conducting interviews.
The building is a total loss.