The three-storey building was evacuated at about 11:30 p.m. PT when flames broke out in one of the suites.
Assistant fire Chief Ron Hull says once the fire was extinguished, crews determined an unattended pot on a stove was to blame.
"If you are going to be cooking with oil, it's usually better to use an approved deep fryer unit," Hull said.
"Oil ... in an open pot left unattended can spontaneously ignite if it gets too hot. So just be cautious when using oil."
Hull says the suite where the fire started is completely destroyed, and 12 other units have significant smoke and water damage.
No one was injured in the blaze.