La Llavor dels Orígens has 4 places in Barcelona. One as described here, one in Gracia, and two next door in Born. They serve typical Catalan food.
Service is very friendly and the dishes are very well prepared and presented. It's all fresh and tastes extremely good. The prices are not cheap but for what you get rather low. I have eaten there 4 times with different people and all of them including me left very happy.
For me the best place for Catalan cuisine.