There's a place in Falset called Quintana (or something like that). They serve vegetarian and non-v. They have a good reputation. I had lunch there once and it was on a par with other mid price restaurants. The family also owns and runs a health food shop.

I'm not really a good restaurant critic as I nearly always leave feeling mild disappointment, maybe because the really good meals I've had were so much better than the good ones.

I don't know where you are, but if you're in Tortosa, it's a bit of a hike to Falset.