You haven't truly experienced Québec if you haven't had 'poutine.' It's the provincial road-side fast-food par excellence: french fries ("des frites") topped with fresh cheese-curds ("fromage en grains," or "squeakers" as they're known in some parts of the U.S.) and then doused with hot brown gravy ("le gravy" in Québecois French)!
Fast-food chains (even in English-speaking Canada) sell it, at least one up-scale restaurant in Montréal has adapted it, adding foie gras (!), but the best way to eat it--quick, before the fries get too mushy--is at a roadside "casse-croûte" on the edge of some rural highway.
Here, at the "Casse-croûte des Appalaches," on provincial route 212, just a few miles from the border with Maine, this was my last chance to indulge before crossing back into the U.S. It may be artery-clogging, mon ami, but once in a while--bon appétit!