When in need of a good dose of sugar, Tella's is definitely the place. They were closed during the winter and have reopened recently. I think it's best to check their Facebook page if you want to visit as they have specific opening hours.
Tella's is located on Beaubien E. there's no metro around, the closest one is Langelier then you can either take the bus #33 or walk... I got there on a Saturday around 3 pm, there weren't many people but I've noticed that they have a huge terrace, so that's good news for the upcoming summer.
I ordered a Bombatella and a Cannelloni Alla Nutella (app.19$): The Bombatella is a decadent chocolate shake with a huge doughnut on top which is fiiiiiiillllllled with Nutella (had to stress on that one, just so that you know what you're getting yourself into when ordering it lol), I really enjoyed the shake which was very creamy. The Cannelloni is filled with apple and Nutella and comes with gelato, my main comment about this dessert is that there was a little bit too much sugar but the combination of apple and Nutella is an awesome idea.
This being said, it was a great experience and the staff was very nice...Needless to say that I will be back!