Maybe it's too late since it's already July, but anyway the info might be useful to other people.
I've lived in Quebec City my whole life, but I've only been vegan since January, so while I know the city well I don't know everything about vegan options.
The only vegetarian restaurant in Quebec City is Restaurant Zen. It has vegan options but I think you have to ask what is vegan.
Non-vegetarian restaurants known for offering at least one vegan option are Le Tiers-temps, which just opened, and Café Babylone, which I think is in vacation right now.
I must admit I haven't eaten in either of these yet (I haven't many occasions of eating out). I usually eat at Thai Express (vegetarian options here
) when I'm at the mall or something. You can get frozen soygourt (called Tofrui) at La Crémière, which tastes good.
There is a vegan potluck nearly every month. The next one is on August 9th, I can give you details if you will still be there by then.
You can buy vegan food at health food stores: Aliments de santé Laurier, Le Crac and Accomodation bio. Aliments de santé Laurier is the biggest.
There are vegan restaurants in Montreal. You can find them on this site
. I haven't been to Montreal in a while so I never tried one. Lucky Montrealers.
And in Rimouski, a small city (much) farther north, Parfum de Corée (Korean food) is simply delicious. It offers three vegan main meals and one dessert (you have to ask what is vegan). And the boulangerie Les baguettes en l'air sells a variety of good vegan muffins (they're not advertized as vegan, you have to ask to make sure).