El Palenque, 653 St. Clair Avenue West (east of Christie), Toronto, Ontario M6C 1A7, 416.656.0725; fax 416.656.3757
El Palenque, a family-owned business, bills itself as an "Authentic Mexican Restaurant." While the waitress was not familiar with Celiac Disease or gluten, she was able to confirm the ingredients of several dishes. Reservations are recommended, but just be sure not to accept a seat in the basement. Even if you are not afflicted from claustrophobia, you'll run away screaming and agitated before you ever get to taste the food. (There is a second location, which I have never visited: 9 Milvan Avenue (Weston Road and Finch), Toronto, 416-740-9718). Now has a lengthy review.
The second time I visited this place, I was less impressed. That post is here.