After eating at many Montreal restaurants, this became my favorite. The 'Maison du Ravioli' was spectacular, almost melting in the mouth. The ravioli are filled with 3 kinds of meats and served in a veal/mushroom reduction. The menu is the same for lunch and dinner.
As in many Montreal restaurants, most dress nicely for dinner, but they will allow people with t-shirts in.
If you are in Montreal, go here. If you are not in Montreal, get yourself to Montreal and eat here.