Guilty and pleasure at the same time. Frequent consumption not advised.
La Banquise is the de facto place for poutine in Montreal. In fact, you could almost consider it a tourist attraction! It is known for its 24hr service of delicious but gluttonous fries topped with gravy, cheese curds, and other toppings of your choosing.
The best time to visit this jolly spot is after a crazy night out, at around 3 or 4 in the morning (when everyone is hammered beyond repair). But beware, you'll probably have to wait in line for about 30 minutes before you get a seat.