There are two pop up kiosks outside of Union Station at the "food market" so I didn't have to brave any line-ups. Just walked up at around 11:30am on a weekday and left with a quarter cheesecake slice (you can also get a whole one).
It has a slight faint cheese flavour...but more fluffy egg than cheesecake. Overall, I thought it was just ok. I wouldn't buy it again but will likely try the matcha cafe one day (when there are no lineups!).