good/authentic tortilla espanola?

I want tortilla and sangria, like I could get in one of the cuevas in Madrid. I want it so much. Most Spanish food in SF is higher brow.

Alegrias is closed. I used to love Las Ramblas, sigh, long closed. I used to go to Canela (mostly because I can walk there) which was overpriced for what it was, but the last time I went, the food was so bad that I resolved never to go back. Please help.