WATCH: Fergie Sings 'Monster Mash'

It's officially Halloween. So while you rock your costume and kick back with some candy, you can have the soundtrack to your frightful day be Fergie singing her favourite Halloween song: "Monster Mash."

Fun fact: "Monster Mash" is indeed a Halloween classic, as it turned 55 years old this year. 

But aside from her favourite Halloween song, we found out about some of Fergie’s throwback costumes and Halloween memories. 

“One time, my mom, I think she was having a joke about it, she put me in ... it was like a satin devil kind of costume, and she put me on roller skates, and she made this costume, she put the letters on the back ... and I was a 'Speed Demon.' And, yeah, that definitely has levels,” she recalled.

Fergie added: “The amusement park is called Knott's Berry Farm. During Halloween time, it's called Knott's Scary Farm. And it was always a cool place to go and flirt … we would go find cute boys, and maybe kiss them at night. But you go to this place, and there were all these ghouls and goblins that would jump out at you. And there were haunted houses you could go through, and get scared. It was fun ... to go flirt and fright together.”

Original article at iHeartRadio