When you do a Yelp search for the best rated place in Toronto, Fahrenheit Coffee is at the top of the list. Which is especially cool when they are literally across the street from your hotel!
The staff (two people when I was there) were incredibly friendly, asked me and my friends about our trip(s), made suggestions, and most importantly... made an incredible chai tea latte. It was so subtle, and not at all overly sugary like 99% of the mass produced chai liquid garbage in most coffee houses and/or chains. Possibly the best I've ever had. I also had a muffin that spoke to me on about 12 different levels.
It's a tiny place you could very easily miss, but that kind of adds to the charm in my opinion. A place this good exists on reputation, and doesn't need flashy signs and advertisements.