The BF is a vegetarian, so while in Paris we are always on the lookout for anything vegetarian -- and granted, in a foodie city like Paris, it was difficult to find. We got several glowing recommendations for Le Grenier de Notre Dame (located in the 5th arrondissement). Unfortunately, we never made it there, but...here's a video I located. Next time eating at this restaurant will be a must!
If you're looking for a vegetarian restaurant in Paris, be sure to make note of this one