But, as we're sure you'll all know by now, it wasn't just any old make-up tutorial. The 10-minute video, which has now gone viral with almost 40 million hits, reveals the make-up tricks she uses to hide her acne.
The young teen, now 19-years-old, bravely revealed her make-up free self on camera, exposing the severe spots marking the skin on her face, neck and back.
Since then, Cassandra has garnered huge media attention, revealing in interviews that she endured years of bullying over her cystic acne, which was diagnosed at 14.
But it seems that the 'bullied acne-ridden teen', as she's become affectionately known in the papers, has had the last laugh having just been booked as a model at New York Fashion Week.
At STYLE360 at the Metropolitan Pavilion in Chelsea, the 5'11 brunette confidently hit the catwalk for US label Boy Meets Girl, showcasing pieces from their spring/summer 2013 collection at one of the biggest fashion events in the world.
And, as well as attracting attention from UK model agency Talent Management, Cassandra has had a similar reception in the US, having been signed by a number of model agencies across the states.
Since being signed, she's already bagged some pretty impressive photographic modelling jobs, including working for contemporary fashion brand Bebe and world-famous car manufacturer Range Rover.
But the recent Boy Meets Girl job marked her first catwalk experience. Discussing the job at NYFW, she told the New York Post: "It feels like a dream to be here during Fashion Week... I am a different person from who I used to be because I've got so much more confidence now."
Since posting that initial video, the teen model has shared more of her tips on her YouTube channel 'diamondsandheels14', and the team at the model agency can't wait to see more!
Talent Management is a Government regulated modelling Employment Agency and we have been successfully placing many of our men, women, and child models in paid, part-time modelling work for more than 20 years.
If you are looking to find a model, become a model, or learn more about the options available to you (or someone you know), then please visit us at - http://www.talentmanagement.com/